CONTROL, ANALYSIS,AND TESTING

CHEMICAL ANALYSIS OF PLATING SOLUTIONS

by Charles RosensteinShellcase Ltd., Jerusalem, Israel

and Stanley HirschLeeam Consultants Ltd., New Rochelle, N.Y.

Plating solutions must be routinely analyzed in order to maintain the recommended bathformulation and to preempt the occurrence of problems related to improper levels of bathconstituents. Contaminant levels in the solutions must also be monitored. Manufacturers ofplating systems establish optimum specifications to ensure maximum solution efficiency anduniformity of deposits. The various factors that cause the concentrations of bath constituentsto deviate from their optimum values are as follows:

1. drag-out;2. solution evaporation;3. chemical decomposition; and4. unequal anode and cathode efficiencies.

A current efficiency problem is recognized by gradual but continuous changes in pH,metal content, or cyanide content (see Table I).

The techniques employed for the quantitative analysis of plating solutions are classifiedas volumetric (titrimetric), gravimetric, and instrumental. Volumetric and gravimetricmethods are also known as “wet” methods. The analyst must select the method that is bestsuited and most cost effective for a particular application.

The wet methods outlined here are simple, accurate, and rapid enough for practically allplating process control. They require only the common analytical equipment found in thelaboratory, and the instructions are sufficiently detailed for an average technician to followwithout any difficulty . The determination of small amounts of impurities and uncommon

Table I . Problems Caused by Unequal Anode andCathode Efficiencies

Problem Cause

High pH High anode efficiencyLow pH High cathode efficiencyHigh metal content High anode efficiencyLow metal content High cathode efficiencyHigh free cyanide Low anode efficiencyLow free cyanide High anode efficiency

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metals should be referred to a competent laboratory, as a high degree of skill and chemicalknowledge are required for the determination of these constituents.

Hull cell testing (see the section on plating cells elsewhere in thisGuidebook) enables theoperator to observe the quality of a deposit over a wide current density range.

VOLUMETRIC METHODS

When titrants composed of standard solutions are added to a sample that contains acomponent whose concentration is to be quantitatively determined, the method is referred toas a volumetric method. The component to be determined must react completely with thetitrant in stoichiometric proportions. From the volume of titrant required, the component’sconcentration is calculated. The simplicity, quickness, and relatively low cost of volumetricmethods make them the most widely used for the analysis of plating and related solutions.

Volumetric methods involve reactions of several types: oxidation-reduction, acid-base,complexation, and precipitation. Indicators are auxiliary reagents, which usually signify theendpoint of the analysis. The endpoint can be indicated by a color change, formation of aturbid solution, or the solubilization of a turbid solution.

Some volumetric methods require little sample preparation, whereas others may requireextensive preparation. Accuracy decreases for volumetric analyses of components found inlow concentrations, as endpoints are not as easily observed as with the components found inhigh concentrations.

Volumetric methods are limited in that several conditions must be satisfied. Indicatorsshould be available to signal the endpoint of the titration. The component-titrant reactionshould not be affected by interferences from other substances found in the solution.

GRAVIMETRIC METHODS

In gravimetric methods, the component being determined is separated from othercomponents of the sample by precipitation, volatilization, or electroanalytical means.Precipitation methods are the most important gravimetric methods. The precipitate is usuallya very slightly soluble compound of high purity that contains the component. The weight ofthe precipitate is determined after it is filtered from solution, washed, and dried. Gravimetricmethods are used to supplement the available volumetric methods.

Limitations of gravimetric methods include the requirement that the precipitatedcomponent has an extremely low solubility. The precipitate must also be of high purity andbe easily filterable.

Species that are analyzed gravimetrically include chloride, sulfate, carbonate, phosphate,gold, and silver.

INSTRUMENTAL METHODS

Instrumental methods differ from wet methods in that they measure a physical propertyrelated to the composition of a substance, whereas wet methods rely on chemical reactions.The selection of an instrument for the analysis of plating solutions is a difficult task. Analystsmust decide if the cost is justified and if the analytical instrument is capable of analyzing forthe required substances with a high degree of accuracy and precision. Instruments coupled tocomputers can automatically sample, analyze, and record results. Mathematical errors areminimized and sample measurements are more reproducible than with wet methods.Instrumental methods are also extremely rapid when compared with wet methods.

Unlike humans, instruments cannot judge. They cannot recognize improper samplepreparation or interfering substances. Erroneous results are sometimes produced by electronicand mechanical malfunctions.

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Analytical instruments frequently used in the analysis of plating solutions can becategorized as spectroscopic, photometric, chromatographic, and electroanalytical. Spectro-scopic methods (flame photometry, emission spectrometry, X-ray fluorescence, mass spec-trometry, and inductively coupled plasma) are based on the emission of light. Photometricmethods (spectrophotometry, colorimetry, and atomic absorption) are based on the absorptionof light. Chromatographic methods (ion chromatography) involve the separation of substancesfor subsequent identification. Electroanalytical methods (potentiometry, conductometry,polarography, amperometry, and electrogravimetry) involve an electric current in the courseof the analysis.

The instrumental methods, comprehensively reviewed below, are most applicable toplating environments.

SPECTROSCOPIC METHODS

Spectroscopy is the analysis of a substance by the measurement of emitted light. Whenheat, electrical energy, or radiant energy is added to an atom, the atom becomes excited andemits light. Excitation can be caused by a flame, spark, X-rays, or an AC or DC arc. Theelectrons in the atom are activated from their ground state to unstable energy shells of higherpotential energy. Upon returning to their ground state, energy is released in the form ofelectromagnetic radiation.

Because each element contains atoms with different arrangements of outermost elec-trons, a distinct set of wavelengths is obtained. These wavelengths, from atoms of severalelements, are separated by a monochromator such as a prism or a diffraction grating.Detection of the wavelengths can be accomplished photographically (spectrograph) or viadirect-reading photoelectric detectors (spectrophotometers). The measurement of intensityemitted at a particular wavelength is proportional to the concentration of the element beinganalyzed.

An advantage of spectroscopy is that the method is specific for the element beinganalyzed. It permits quantitative analysis of trace elements without any preliminary treatmentand without prior knowledge as to the presence of the element. Most metals and somenonmetals may be analyzed. Spectroscopic analysis is also useful for repetitive analyticalwork.

Disadvantages of spectroscopic analysis include the temperature dependence of intensitymeasurements, as intensity is very sensitive to small fluctuations in temperature. The accuracyand precision of spectrographic methods is not as high as some spectrophotometric methodsor wet analyses. Spectrographic methods are usually limited to maximum element concen-trations of 3%. Additionally, sensitivity is much smaller for elements of high energy (e.g.,zinc) than for elements of low energy (e.g., sodium).

Applications of spectroscopy include the analysis of major constituents and impurities inplating solutions, and of alloy deposits for composition.

Flame PhotometryIn flame photometry (FP), a sample in solution is atomized at constant air pressure and

introduced in its entirety into a flame as a fine mist. The temperature of the flame(1,800–3,100˚K) is kept constant. The solvent is evaporated and the solid is vaporized andthen dissociated into ground state atoms. The valence electrons of the ground state atoms areexcited by the energy of the flame to higher energy levels and then fall back to the groundstate. The intensities of the emitted spectrum lines are determined in the spectrograph ormeasured directly by a spectrophotometer.

The flame photometer is calibrated with standards of known composition and concen-tration. The intensity of a given spectral line of an unknown can then be correlated with theamount of an element present that emits the specific radiation.

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Physical interferences may occur from solute or solvent effects on the rate of transportof the sample into the flame. Spectral interferences are caused by adjacent line emissionswhen the element being analyzed has nearly the same wavelength as another element.Monochromators or the selection of other spectral lines minimize this interference. Ionizationinterferences may occur with the higher temperature flames. By adding a second ionizableelement, the interferences due to the ionization of the element being determined areminimized.

An advantage of FP is that the temperature of the flame can be kept more nearly constantthan with electric sources. A disadvantage of the method is that the sensitivity of the flamesource is many times smaller than that of an electric arc or spark.

FP is used for the analysis of aluminum, boron, cadmium, calcium, chromium, cobalt,copper, indium, iron, lead, lithium, magnesium, nickel, palladium, platinum, potassium,rhodium, ruthenium, silver, sodium, strontium, tin, and zinc.

Emission SpectrometryIn emission spectrometry (ES), a sample composed of a solid, cast metal or solution is

excited by an electric discharge such as an AC arc, a DC arc, or a spark. The sample is usuallyplaced in the cavity of a lower graphite electrode, which is made positive. The uppercounterelectrode is another graphite electrode ground to a point. Graphite is the preferredelectrode material because of its ability to withstand the high electric discharge temperatures.It is also a good electrical conductor and does not generate its own spectral lines.

The arc is started by touching the two graphite electrodes and then separating them. Theextremely high temperatures (4,000–6,000˚K) produce emitted radiation higher in energy andin the number of spectral lines than in flame photometry. Characteristic wavelengths fromatoms of several elements are separated by a monochromator and are detected by spectro-graphs or spectrophotometers. Qualitative identification is performed by using availablecharts and tables to identify the spectral lines that the emission spectrometer sorts outaccording to their wavelength. The elements present in a sample can also be qualitativelydetermined by comparing the spectrum of an unknown with that of pure samples of theelements. The density of the wavelengths is proportional to the concentration of the elementbeing determined. Calibrations are done against standard samples.

ES is a useful method for the analysis of trace metallic contaminants in plating baths. The“oxide” method is a common quantitative technique in ES. A sample of the plating bath isevaporated to dryness and then heated in a muffle furnace. The resultant oxides are mixedwith graphite and placed in a graphite electrode. Standards are similarly prepared and a DCarc is used to excite the sample and standards.

X-ray FluorescenceX-ray fluorescence (XRF) spectroscopy is based on the excitation of samples by an

X-ray source of sufficiently high energy, resulting in the emission of fluorescent radiation.The concentration of the element being determined is proportional to the intensity of itscharacteristic wavelength. A typical XRF spectrometer consists of an X-ray source, a detector,and a data analyzer.

Advantages of XRF include the nondestructive nature of the X-rays on the sample. XRFis useful in measuring the major constituents of plating baths such as cadmium, chromium,cobalt, gold, nickel, silver, tin, and zinc. Disadvantages of XRF include its lack of sensitivityas compared with ES.

X-ray spectroscopy is also used to measure the thickness of a plated deposit. The X-raydetector is placed on the wavelength of the element being measured. The surface of thedeposit is exposed to an X-ray source and the intensity of the element wavelength is measured.A calibration curve is constructed for intensity against thickness for a particular deposit.Coating compositions can also be determined by XRF.

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Mass SpectrometryIn mass spectrometry (MS), gases or vapors derived from liquids or solids are bombarded

by a beam of electrons in an ionization chamber, causing ionization and a rupture of chemicalbonds. Charged particles are formed, which may be composed of elements, molecules, orfragments. Electric and magnetic fields then separate the ions according to their mass tocharge ratios (m/e). The amount and type of fragments produced in an ionization chamber, fora particular energy of the bombarding beam, are characteristic of the molecule; therefore,every chemical compound has a distinct mass spectrum. By establishing a mass spectrum ofseveral pure compounds, an observed pattern allows identification and analysis of complexmixtures.

The mass spectrum of a compound contains the masses of the ion fragments and therelative abundances of these ions plus the parent ion. Dissociation fragments will alwaysoccur in the same relative abundance for a particular compound.

MS is applicable to all substances that have a sufficiently high vapor pressure. Thisusually includes substances whose boiling point is below 450˚C. MS permits qualitative andquantitative analysis of liquids, solids, and gases.

Inductively Coupled PlasmaInductively coupled plasma (ICP) involves the aspiration of a sample in a stream of

argon gas, and then its ionization by an applied radio frequency field. The field is inductivelycoupled to the ionized gas by a coil surrounding a quartz torch that supports and encloses theplasma. The sample aerosol is heated in the plasma, the molecules become almost completelydissociated and then the atoms present in the sample emit light at their characteristicfrequencies. The light passes through a monochromator and onto a detector.

The high temperature (7,000˚K) of the argon plasma gas produces efficient atomicemission and permits low detection limits for many elements. As with atomic absorption(AA), ICP does not distinguish between oxidation states (e.g., Cr31 and Cr61) of the sameelement—the total element present is determined. Advantages of ICP include completeionization and no matrix interferences as in AA. ICP allows simultaneous analysis of manyelements in a short time. It is sensitive to part-per-billion levels.

Disadvantages of ICP include its high cost and its intolerance to samples with greaterthan 3% dissolved solids. Background corrections usually compensate for interferences due tobackground radiation from other elements and the plasma gases. Physical interferences, dueto viscosity or surface tension, can cause significant errors. These errors are reduced bydiluting the sample. Although chemical interferences are insignificant in the ICP method, theycan be greatly minimized by careful selection of the instrument’s operating conditions, bymatrix matching, or by buffering the sample.

ICP is applicable to the analysis of major components and trace contaminants in platingsolutions. It is also useful for waste-treatment analysis.

PHOTOMETRIC METHODS

Photometric methods are based on the absorption of ultraviolet (200–400 nm) or visible(400–1,000 nm) radiant energy by a species in solution. The amount of energy absorbed isproportional to the concentration of the absorbing species in solution. Absorption isdetermined spectrophotometrically or colorimetrically.

The sensitivity and accuracy of photometric methods must be frequently checked bytesting standard solutions in order to detect electrical, optical, or mechanical malfunctions inthe analytical instrument.

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Spectrophotometry and ColorimetrySpectrophotometryinvolves analysis by the measurement of the light absorbed by a

solution. The absorbance is proportional to the concentration of the analyte in solution.Spectrophotometric methods are most often used for the analysis of metals with concentra-tions of up to 2%.

Spectrophotometers consist of a light source (tungsten or hydrogen), a monochromator,a sample holder, and a detector. Ultraviolet or visible light of a definite wavelength is usedas the light source. Detectors are photoelectric cells that measure the transmitted (unabsorbed)light. Spectrophotometers differ from photometers in that they utilize monochromators,whereas photometers use filters to isolate the desired wavelength region. Filters isolate awider band of light.

In spectrophotometric titrations, the cell containing the analyte solution is placed in thelight path of a spectrophotometer. Titrant is added to the cell with stirring, and the absorbanceis measured. The endpoint is determined graphically. Applications of this titration include theanalysis of a mixture of arsenic and antimony and the analysis of copper with ethylenediamine tetra acetic acid (EDTA).

The possibility of errors in spectrophotometric analyses is increased when numerousdilutions are required for an analysis.

Colorimetry involves comparing the color produced by an unknown quantity of asubstance with the color produced by a standard containing a known quantity of thatsubstance. When monochromatic light passes through the colored solution, a certain amountof the light, proportional to the concentration of the substance, will be absorbed. Substancesthat are colorless or only slightly colored can be rendered highly colored by a reaction withspecial reagents.

In the standard series colorimetric method, the analyte solution is diluted to a certainvolume (usually 50 or 100 ml) in a Nessler tube and mixed. The color of the solution iscompared with a series of standards similarly prepared. The concentration of the analyteequals the concentration of the standard solution whose color it matches exactly. Colors canalso be compared to standards via a colorimeter (photometer), comparator, or spectropho-tometer.

The possible errors in colorimetric measurements may arise from the following sources:turbidity, sensitivity of the eye or color blindness, dilutions, photometer filters, chemicalinterferences, and variations in temperature or pH.

Photometric methods are available for the analysis of the following analytes:

Anodizing solutions: Fe, Cu, MnBrass solutions: FeCadmium solutions: Fe, Ti, Zn, Cu, NiChromium solutions: Cr, Fe, Ni, Cu, SeAcid copper solutions: Cl, FeAlkaline copper solutions: Fe, SeGold solutions: Au, Ni, In, Co, Cu, Fe, PO4

Iron solutions: Mn, NH3Lead and tin-lead solutions: PbNickel solutions: Cr, Cu, Zn, Fe, Co, NH3Palladium solutions: Pd, Cr, NH3Platinum solutions: PtRhodium solutions: RhSilver solutions: Ni, Cu, SbAcid tin solutions: Fe, CuAlkaline tin solutions: Cu, Pb, Zn

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Acid zinc solutions: Cu, FeAlkaline zinc solutions: Cu, FeWastewater: Cr61, Ni, Cu, Fe, Zn, Pb, Al, B, NO3, NO2, PO4, Cl, CN, wetting agents.

Atomic AbsorptionMetals in plating and related solutions can be readily determined by AA spectropho-

tometry. Optimum ranges, detection limits, and sensitivities of metals vary with the variousavailable instruments.

In direct-aspiration atomic absorption(DAAA) analysis, the flame (usually air-acetylene or nitrous oxide-acetylene) converts the sample aerosol into atomic vapor, whichabsorbs radiation from a light source. A light source from a hollow cathode lamp or anelectrodeless discharge lamp is used, which emits a spectrum specific to the element beingdetermined. The high cost of these lamps is a disadvantage of the AA method. A detectormeasures the light intensity to give a quantitative determination.

DAAA is similar to flame photometry in that a sample is aspirated into a flame andatomized. The difference between the two methods is that flame photometry measures theamount of emitted light, whereas DAAA measures the amount of light absorbed by theatomized element in the flame. In DAAA, the number of atoms in the ground state is muchgreater than the number of atoms in any of the excited states of the spectroscopic methods.Consequently, DAAA is more efficient and has better detection limits than the spectroscopicmethods.

Spectral interferences occur when a wavelength of an element being analyzed is close tothat of an interfering element. The analysis will result in an erroneously high measurement.To compensate for this interference, an alternate wavelength or smaller slit width is used.

When the physical properties (e.g., viscosity) of a sample differ from those of thestandard, matrix interferences occur. Absorption can be enhanced or suppressed. To overcomethese interferences, matrix components in the sample and standard are matched or a releaseagent, such as EDTA or lanthanum, is added.

Chemical interferences are the most common interferences encountered in AA analysis.They result from the nonabsorption of molecularly bound atoms in the flame. Theseinterferences are minimized by using a nitrous oxide-acetylene flame instead of anair-acetylene flame to obtain the higher flame temperature needed to dissociate the moleculeor by adding a specific substance (e.g., lanthanum) to render the interferant harmless.Chemical interferences can also be overcome by extracting the element being determined orby extracting the interferant from the sample.

The sensitivity and detection limits in AA methods vary with the instrument used, thenature of the matrix, the type of element being analyzed, and the particular AA techniquechosen. It is best to use concentrations of standards and samples within the optimumconcentration range of the AA instrument. When DAAA provides inadequate sensitivity,other specialized AA methods, such as graphite furnace AA, cold vapor AA, or hydride AA,are used.

In graphite furnace AA(GFAA), the flame that is used in DAAA is replaced with anelectrically heated graphite furnace. A solution of the analyte is placed in a graphite tube inthe furnace, evaporated to dryness, charred, and atomized. The metal atoms being analyzedare propelled into the path of the radiation beam by increasing the temperature of the furnaceand causing the sample to be volatilized. Only very small amounts of sample are required forthe analysis.

GFAA is a very sensitive technique and permits very low detection limits. The increasedsensitivity is due to the much greater occupancy time of the ground state atoms in the opticalpath as compared with DAAA. Increased sensitivity can also be obtained by using largersample volumes or by using an argon-hydrogen purge gas mixture instead of nitrogen.Because of its extreme sensitivity, determining the optimum heating times, temperature, andmatrix modifiers is necessary to overcome possible interferences.

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Interferences may occur in GFAA analysis due to molecular absorption and chemicaleffects. Background corrections compensate for the molecular absorption interference.Specially coated graphite tubes minimize its interaction with some elements. Gradual heatinghelps to decrease background interference, and permits determination of samples withcomplex mixtures of matrix components.

The GFAA method has been applied to the analysis of aluminum, antimony, arsenic,barium, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum,nickel, selenium, silver, and tin.

Cold vapor atomic absorption(CVAA) involves the chemical reduction of mercury orselenium by stannous chloride and its subsequent analysis. The reduced solution is vigorouslystirred in the reaction vessel to obtain an equilibrium between the element in the liquid andvapor phases. The vapor is then purged into an absorption cell located in the light path of aspectrophotometer. The resultant absorbance peak is recorded on a strip chart recorder.

The extremely sensitive CVAA procedure is subject to interferences from some organics,sulfur compounds, and chlorine. Metallic ions (e.g., gold, selenium), which are reduced to theelemental state by stannous chloride, produce interferences if they combine with mercury.

Hydride atomic absorption(HAA) is based on chemical reduction with sodiumborohydride to selectively separate hydride-forming elements from a sample. The gaseoushydride that is generated is collected in a reservoir attached to a generation flask, and is thenpurged by a stream of argon or nitrogen into an argon-hydrogen-air flame. This permitshigh-sensitivity determinations of antimony, arsenic, bismuth, germanium, selenium, tellu-rium, and tin.

The HAA technique is sensitive to interferences from easily reduced metals such assilver, copper, and mercury. Interferences also arise from transition metals in concentrationsgreater than 200 mg/L and from oxides of nitrogen.

Ion ChromatographyIn ion chromatography (IC), analytes are separated with an eluent on a chromatographic

column based on their ionic charges. Because plating solutions are water based, the solublecomponents must be polar or ionic; therefore, IC is applicable to the analysis of plating andrelated solutions.

Ion chromatographs consist of a sample delivery system, a chromatographic separationcolumn, a detection system, and a data handling system.

IC permits the rapid sequential analysis of multiple analytes in one sample. The variousdetectors available, such as UV-visible, electrochemical, or conductivity, allow for specificdetection in the presence of other analytes. IC is suitable for the analysis of metals, anionicand cationic inorganic bath constituents, and various organic plating bath additives. It is alsoused for continuous on-line operations.

Interferences arise from substances that have retention times coinciding with that of anyanion being analyzed. A high concentration of a particular ion may interfere with theresolution of other ions. These interferences can be greatly minimized by gradient elution orsample dilution.

IC has been applied to the analysis of the following analytes in plating and relatedsolutions:

Metals: Aluminum, barium, cadmium, calcium, trivalent and hexavalent chromium,cobalt, copper, gold, iron, lead, lithium, magnesium, nickel, palladium, platinum, silver, tin,zinc.

Ions:Ammonium, bromide, carbonate, chloride, cyanide, fluoborate, fluoride, hypophos-phite, nitrate, nitrite, phosphate, potassium, sodium, sulfate, sulfide, sulfite.

Acid Mixtures:Hydrofluoric, nitric, and acetic acids.Organics:Brighteners, surfactants, organic acids.

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ELECTROANALYTICAL METHODS

Electroanalytical methods involve the use of one or more of three electricalquantities—current, voltage, and resistance. These methods are useful when indicators for atitration are unavailable or unsuitable. Although trace analysis may be done quite well byspectroscopic or photometric methods, electroanalytical methods offer ease of operation andrelatively lower costs of purchase and maintenance.

PotentiometryPotentiometry involves an electrode that responds to the activity of a particular group of

ions in solution. Potentiometric methods correlate the activity of an ion with its concentrationin solution.

In potentiometric titrations, titrant is added to a solution and the potential between anindicator and reference electrode is measured. The reaction must involve the addition orremoval of an ion for which an electrode is available. Acid-base titrations are performed witha glass indicator electrode and a calomel reference electrode. The endpoint corresponds to themaximum rate of change of potential per unit volume of titrant added.

Advantages of potentiometric titrations include its applicability to colored, turbid, orfluorescent solutions. It is also useful in situations where indicators are unavailable.

The sensitivity of potentiometric titrations is limited by the accuracy of the measurementof electrode potentials at low concentrations. Solutions that are more dilute than 1025 Ncannot be accurately titrated potentiometrically. This is because the experimentally measuredelectrode potential is a combined potential, which may differ appreciably from the trueelectrode potential. The difference between the true and experimental electrode potentials isdue to the residual current, which arises from the presence of electroactive trace impurities.

The direct potentiometric measurement of single ion concentrations is done with ionselective electrodes (ISEs). The ISE develops an electric potential in response to the activityof the ion for which the electrode is specific. ISEs are available for measuring calcium,copper, lead, cadmium, ammonia, bromide, nitrate, cyanide, sulfate, chloride, fluoride, andother cations and anions.

Cation ISEs encounter interferences from other cations, and anion ISEs encounterinterferences from other anions. These interferences can be eliminated by adjusting the samplepH or by chelating the interfering ions. ISE instructions must be reviewed carefully todetermine the maximum allowable levels of interferants, the upper limit of the single ionconcentration for the ISE, and the type of media compatible with the particular ISE.

Some of the solutions that can be analyzed by potentiometric methods are:

Anodizing solutions: Al, H2SO4, C2H2O4, CrO3, ClBrass solutions: Cu, Zn, NH3, CO3

Bronze solutions: Cu, Sn, NaOH, NaCN, Na2CO3

Chromium solutions: Cr, ClCadmium solutions: Cd, NaOH, NaCN, Na2CO3

Acid copper solutions: ClAlkaline copper solutions: NaOH, NaCN, Na2CO3

Gold solutions: Au, Ag, Ni, CuLead and tin/lead solutions: Pb, Sn, HBF4

Nickel solutions: Co, Cu, Zn, Cd, Cl, H3BO3

Silver solutions: Ag, Sb, NiAcid tin solutions: Sn, HBF4, H2SO4

Alkaline tin solutions: Sn, NaOH, NaCO3, ClZinc solutions: Zn

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ConductometryElectrolytic conductivity measures a solution’s ability to carry an electric current. A

current is produced by applying a potential between two inert metallic electrodes (e.g.,platinum) inserted into the solution being tested. When other variables are held constant,changes in the concentration of an electrolyte result in changes in the conductance of electriccurrent by a solution.

In conductometric titrations, the endpoint of the titration is obtained from a plot ofconductance against the volume of titrant. Excessive amounts of extraneous foreignelectrolytes can adversely affect the accuracy of a conductometric titration.

Conductometric methods are used when wet or potentiometric methods give inaccurateresults due to increased solubility (in precipitation reactions) or hydrolysis at the equivalencepoint. The methods are accurate in both dilute and concentrated solutions, and they can alsobe used with colored solutions.

Conductometric methods have been applied to the analysis of Cr, Cd, Co, Fe, Ni, Pb, Ag,Zn, CO3, Cl, F, and SO4.

PolarographyIn polarography, varying voltage is applied to a cell consisting of a large mercury anode

(reference electrode) and a small mercury cathode (indicator electrode) known as a droppingmercury electrode (DME). Consequent changes in current are measured. The large area of themercury anode precludes any polarization. The DME consists of a mercury reservoir attachedto a glass capillary tube with small mercury drops falling slowly from the opening of the tube.A saturated calomel electrode is sometimes used as the reference electrode.

The electrolyte in the cell consists of a dilute solution of the species being determined ina medium of supporting electrolyte. The supporting electrolyte functions to carry the currentin order to raise the conductivity of the solution. This ensures that if the species to bedetermined is charged, it will not migrate to the DME. Bubbling an inert gas, such as nitrogenor hydrogen, through the solution prior to running a polarogram, will expel dissolved oxygenin order to prevent the dissolved oxygen from appearing on the polarogram.

Reducible ions diffuse to the DME. As the applied voltage increases, negligible currentflow results until the decomposition potential is reached for the metal ion being determined.When the ions are reduced at the same rate as they diffuse to the DME, no further increasesin current occur, as the current is limited by the diffusion rate. The half-wave potential is thepotential at which the current is 50% of the limiting value.

Polarograms are obtained by the measurement of current as a function of appliedpotential. Half-wave potentials are characteristic of particular substances under specifiedconditions. The limiting current is proportional to the concentration of the substance beingreduced. Substances can be analyzed quantitatively and qualitatively if they are capable ofundergoing anodic oxidation or cathodic reduction. As with other instrumental methods,results are referred to standards in order to quantitate the method.

Advantages of polarographic methods include their ability to permit simultaneousqualitative and quantitative determinations of two or more analytes in the same solution.Polarography has wide applicability to inorganic, organic, ionic, or molecular species.

Disadvantages of polarography include the interferences caused by large concentrationsof electropositive metals in the determination of low concentrations of electronegative metals.The very narrow capillary of the DME occasionally becomes clogged.

Polarographic methods are available for the following solutions:

Anodizing solutions: Cu, Zn, MnBrass solutions: Pb, Cd, Cu, Ni, ZnBronze solutions: Pb, Zn, Al, Cu, NiCadmium solutions: Cu, Pb, Zn, Ni

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Chromium solutions: Cu, Ni, Zn, Cl, SO4Acid copper solutions: Cu, ClAlkaline copper solutions: Zn, Fe, Pb, CuGold solutions: Au, Cu, Ni, Zn, In, Co, CdIron solutions: MnLead and tin-lead solutions: Cu, Cd, Ni, Zn, SbNickel solutions: Cu, Pb, Zn, Cd, Na, Co, Cr, MnPalladium solutions: Pd, Cr31, Cr61

Rhodium solutions: RhSilver solutions: Sb, Cu, CdAcid tin solutions: Sn41, Cu, Ni, ZnAlkaline tin solutions: Pb, Cd, Zn, CuAcid zinc solutions: Cu, Fe, Pb, CdAlkaline zinc solutions: Pb, Cd, CuWastewater: Cd, Cu, Cr31, Ni, Sn, Zn

AmperometryAmperometric titrations involve the use of polarography as the basis of an electrometric

titration. Voltage applied across the indicator electrode (e.g., DME or platinum) and referenceelectrode (e.g., calomel or mercury) is held constant and the current passing through the cellis measured as a function of titrant volume added. The endpoint of the titration is determinedfrom the intersection of the two straight lines in a plot of current against volume of titrantadded. Polarograms are run to determine the optimum titration voltage.

Amperometric titrations can be carried out at low analyte concentrations at whichvolumetric or potentiometric methods cannot yield accurate results. They are temperatureindependent and more accurate than polarographic methods. Although amperometry is usefulfor oxidation-reduction or precipitation reactions, few acid-base reactions are determined bythis method.

Some of the reactions that can be analyzed by amperometric methods are given inTable II.

ElectrogravimetryIn electrogravimetry, the substance to be determined is separated at a fixed potential on

a preweighed inert cathode, which is then washed, dried, and weighed. Requirements for anaccurate electrogravimetric analysis include good agitation, smooth adherent deposits, andproper pH, temperature, and current density.

Table II. Reactions That Can Be Analyzed by Amperometry

Analyte Titrant Supporting Electrolyte

Fluoride Lead nitrate Potassium chlorideGold Hydroquinone Sulfuric acidNickel Dimethylglyoxime ChlorideLead Sodium fluoride ChlorideBromide Silver nitrate Nitric acidCalcium EDTA AmmoniaCadmium EDTA AmmoniaChloride Silver nitrate Nitric acidIndium EDTA Weak acid

EDTA, ethylene diamine tetra acetic acid.

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Advantages of electrogravimetry include its ability to remove quantitatively mostcommon metals from solution. The method does not require constant supervision. Disadvan-tages include long electrolysis times.

Some of the metals that have been determined electrogravimetrically are cadmium,cobalt, copper, gold, iron, lead, nickel, rhodium, silver, tin, and zinc.

SAMPLING

Analyses are accurate only when the sample is truly representative of the solution beinganalyzed. Each tank should have a reference mark indicating the correct level for the solution,and the bath should always be at this level when the sample is taken. Solutions should bestirred before sampling. If there is sludge in the tank, the solution should be stirred at the endof the day and the bath allowed to stand overnight, taking the sample in the morning.

Solutions should be sampled by means of a long glass tube. The tube is immersed in thesolution, the thumb is placed over the upper open end, and a full tube of solution is withdrawnand transferred to a clean, dry container. The solution should be sampled at a minimum of 10locations in the tank to ensure a representative sample. A quart sample is sufficient foranalysis and Hull cell testing, and any remaining solution can be returned to its tank.

STANDARD SOLUTIONS, REAGENTS, AND INDICATORSFOR WET METHODS

Standard solutions, reagents, and indicators can be purchased ready-made from labora-tory supply distributors. Unless a laboratory has the experience and high degree of accuracythat is required in preparing these solutions, it is recommended that they be purchased asprepared solutions. Preparations for all the solutions are given here to enable technicians toprepare or recheck their solutions.

A standard solution is a solution with an accurately known concentration of a substanceused in a volumetric analysis. Standardization of standard solutions requires greater accuracythan routine volumetric analyses. An error in standardization causes errors in all analyses thatare made with the solution; therefore, Primary Standard Grade chemicals should be used tostandardize standard solutions.

The strengths of standard solutions are usually expressed in terms of normality ormolarity. Normalities of standard solutions and their equivalent molarities are listed in TableIII. The methods to standardize all the standard solutions required for the analysis of platingand related solutions are listed in Table IV.

Table III. Molarities and Normalities of Standard Solutions

Standard Solution Formula Normality Molarity

EDTA C10H14O8N2Na2·2H2O 0.2 0.1Ferrous ammonium sulfate FeSO4(NH4)2SO4·6H2O 0.1 0.1Hydrochloric acid HCl 1.0 1.0Iodine I2 0.1 0.1Potassium dichromate K2Cr2O7 0.1 0.02Potassium iodide-iodate KI-KIO3 0.1 0.0167Potassium permanganate KMnO4 0.1 0.02Potassium thiocyanate KSCN 0.1 0.1Silver nitrate AgNO3 0.1 0.1Sodium hydroxide NaOH 1.0 1.0Sodium thiosulfate Na2S2O3·5H2O 0.1 0.1

EDTA, ethylene diamine tetra acetic acid.

532

Indicators are added to solutions in volumetric analyses to show color change or onset ofturbidity, signifying the endpoint of a titration. The indicators required for all of the analyses andtheir preparations are listed in Table V. Analytical Grade chemicals should be used in preparinganalytical reagents (Table VI) and Reagent Grade acids should be used (Table VII). Whenchemicals of lesser purity are used, the accuracy of the results will be diminished.

Tables VIII through XII provide specific methods for testing the constituents ofelectroplating, electroless, and anodizing baths, as well as acid dips and alkaline cleaners.

SAFETY

As with any laboratory procedure, the accepted safety rules for handling acids, bases, andother solutions should be followed. Acids are always added to water, not the reverse. Mouthpipettes should not be used for pipetting plating solutions. Safety glasses should always beworn, and care should be exercised to avoid skin and eye contact when handling chemicals.A fume hood should be used when an analytical method involves the liberation of hazardousor annoying fumes. Laboratory staff should be well versed in the first-aid procedures requiredfor various chemical accidents.

DETERMINATION OF CATHODE EFFICIENCY

The procedure for determining cathode efficiency, using the setup pictured in Fig. 1, isas follows:

1. Connect the copper coulometer in series with the test cell.2. The copper coulometer solution should contain 30 oz/gal copper sulfate pentahydrate

and 8 oz/gal sulfuric acid.3. Use the same anodes, temperature, and agitation in the test solution that are used in

the plating bath.4. Plate at 0.4 A (30 A/ft2) for a minimum of 10 minutes.5. Rinse both cathodes, dry in acetone, and weigh.

% Cathode Efficiency5weight in grams of test metal3 valence of test metal in bath3 3177

weight in grams of copper metal3 atomic weight of test metal

Fig. 1. Test setup for determination of cathode efficiency. Use 500-ml beakers and 13 2-in.brass cathodes. The anodes for the test solution should match that used in the plating bath.Use copper anodes for the coulometer.

533

Tab

leIV

.S

tand

ardi

zatio

nof

Sta

ndar

dS

olut

ions

So

lutio

nR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

e

Ca

lcu

latio

ns

(ml,

N,

M-t

itra

nt;

wt-

sam

ple

ing

ram

s)

0.1

ME

DT

A37

.0g

Na 2

ED

TA

·2H

2O

per

liter

H2O

5.0

gC

aCO 3

diss

olve

din

1:3

HC

land

dilu

ted

to50

0m

lin

avo

lum

etric

flask

.P

ipet

te20

-mls

ampl

e,ad

d10

0m

lH 2O,,a

10m

lpH

10bu

ffer,

and

EB

Tpo

wde

r.

ED

TA

Red

-blu

eM

ED

TA

5(w

tC

aCO 3

3m

lsam

ple)

/(m

lED

TA

350

.05)

0.1

NH

Cl

9m

l36%

HC

lper

liter

H2O

0.2

gN

a 2C

O3,

125

mlH

2O

,an

dbr

omoc

reso

lgre

en.

HC

lB

lue-

gree

nN

HC

l5

(wt

Na 2

CO

3)/

(ml3

0.05

299)

1.0

NH

Cl

89m

l36%

HC

lper

liter

H2O

2.0

gN

a 2C

O3,

125

mlH

2O

,an

dbr

omoc

reso

lgre

en.

HC

lB

lue-

gree

nN

HC

l5

(wt

Na 2

CO

3)/

(ml3

0.05

299)

0.1

NI 1

12.7

gI 2,

24.0

gK

lpe

rlit

erH 2

O

0.2

gA

s 2O

3,

20m

l1.0

NN

aOH

,ge

ntly

heat

until

As

2O

3di

ssol

ves,

cool

,ad

dph

enol

phth

alei

n,1.

0N

HC

ladd

edfr

ompi

nkto

colo

rless

,10

0m

lH2O

,1

mlc

onc.

HC

l,2

gbi

carb

onat

ead

ded

slow

ly,

and

star

chso

lutio

n.

I 2C

olor

less

-blu

eN

I 25

(wt

As 2

O3/

(ml3

0.04

946)

0.01

NH

g(N

O 3) 2

1.08

3g

HgO

,5

ml

50%

HN

O 3pe

rlit

erH

2O

7.5

gK

Cld

isso

lved

inH 2

Oan

ddi

lute

dto

1,00

0m

lin

avo

lum

etric

flask

.P

ipet

te2-

mls

ampl

e,ad

d10

0m

lH 2O,

and

15m

l20%

tric

hlor

oace

ticac

id.

Hg(

NO

3) 2

Col

orle

ss-p

urpl

eN

Hg(

NO 3)

25

(wt

KC

l3

mls

ampl

e)/(

ml

Hg(

NO

) 3) 2

374

.56)

0.1

NK

I-K

IO3

3.6

gK

IO3,

1.0

gN

aOH

,10

.0g

KI

per

liter

H2O

In50

0-m

lfla

skad

d0.

20g

Sn,

100

mlc

onc.

HC

l,2

drop

sS

bCl

3

solu

tion,

let

stan

dat

room

tem

pera

ture

tilld

isso

lved

.A

dd18

0m

lH

2O

,5-

in.

fold

ed“U

”-sh

aped

nick

elst

rip,

and

5.0

gre

duce

diro

npo

wde

r.S

topp

erfla

skw

ithru

bber

stop

per

fitte

dw

ith1 ⁄4-in

.gl

ass

tube

imm

erse

din

toa

satu

rate

dN

aHC

O3

solu

tion.

Hea

tso

lutio

non

hot-

plat

eto

boil

for

20m

inut

esan

dth

enpl

ace

inco

olin

gta

nkan

dal

low

toco

olto

room

tem

pera

ture

.M

ake

sure

glas

sou

tlet

tube

isim

mer

sed

inth

eN

aHC

O 3.R

emov

est

oppe

ran

dad

dst

arch

solu

tion.

KI-

KIO

3C

olor

less

-blu

eN

KI-

KIO

35

(wt

Sn)

/(m

l30.

0593

45)

534

Tab

leIV

.S

tand

ardi

zatio

nof

Sta

ndar

dS

olut

ions

(co

nt.)

So

lutio

nR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

e

Ca

lcu

latio

ns

(ml,

N,

M-t

itra

nt;

wt-

sam

ple

ing

ram

s)

0.1

NK

MnO

4

3.2

gK

MnO

4pe

rlit

erH

2O

Hea

tK

MnO

4so

lutio

nto

near

boili

ngfo

r30

min

utes

and

let

stan

dov

erni

ght.

Filt

erth

roug

ha

sint

ered

glas

scr

ucib

le.

The

n,to

stan

dard

ize:

add

0.2

gN

a2C

2O

4,

200

mlH

2O

,30

ml2

0%H 2

SO

4,

heat

to18

5–19

5˚F

.

KM

nO4

Col

orle

ss-p

ink

NK

MnO

45

(wt

Na 2

C2O

4)/

(ml3

0.06

70)

0.1

NK

SC

N9.

7g

KS

CN

per

liter

H2O

0.3

gA

g,15

ml5

0%H

NO 3

,10

0m

lH2O

,an

dF

AS

.K

SC

NC

olor

less

-red

NK

SC

N5(w

tA

g)/

(ml3

0.10

787)

0.1

AgN

O3

17.0

gA

gNO 3

per

liter

H2O

0.2

gN

aCl,

125

mlH

2O

,an

dK 2

CrO

4.

AgN

O3

Yel

low

-red

NA

gNO 3

5(w

tN

aCl)/

(ml3

0.05

845)

0.1

NN

aOH

4.0

gN

aOH

per

liter

H2O

0.5

gpo

tass

ium

hydr

ogen

phth

alat

e(K

HC

8H

4O

4),

125

mlH

2O

,an

dph

enol

phth

alei

n.N

aOH

Col

orle

ss-p

ink

NN

aOH5

(wt

KH

C8H

4O

4)/

(ml3

0.20

422)

1.0

NN

aOH

40.0

gN

aOH

per

liter

H2O

4.0

gpo

tass

ium

hydr

ogen

phth

alat

e(K

HC

8H

4O

4),

125

mlH

2O

,an

dph

enol

phth

alei

nin

dica

tor.

NaO

HC

olor

less

-pin

kN

NaO

H5(w

tK

HC

8H

4O

4)/

(ml3

0.20

422)

0.1

NN

a 2S 2

O3

25.0

gN

a 2S 2

O3·5

H2

Ope

rlit

erH 2

O

Add

0.1

gN

a 2C

O3

toN

a 2S 2

O3

solu

tion

and

let

stan

dfo

r24

hour

s.T

ost

anda

rdiz

e:ad

d0.

12g

KIO 3,

2g

KI,

25m

lH2O

,an

d8

ml

10%

HC

l.T

itrat

eto

light

yello

ww

ithN

a 2S2O

3an

dad

d2

mls

tarc

hso

lutio

n.

Na 2

S 2O

3B

lue-

colo

rless

NN

a 2S2O

35

(wt

KIO

3)/

(ml3

0.03

567)

0.1

NT

h(N

O 3) 4

14.0

gT

h(N

O3) 4

·4H

2O

per

liter

H2O

5.0

gN

aFdi

ssol

ved

inH 2O

and

dilu

ted

to1,

000

mli

na

volu

met

ricfla

sk.

Pip

ette

10-m

lsam

ple,

add

100

mlH 2O

,al

izar

inin

dica

tor,

2%H

NO

3,

drop

wis

efr

ompi

nkto

yello

w,

and

3m

lflu

orid

ebu

ffer.

Th(

NO

3) 4

Yel

low

-pin

kN

5(w

tN

aFpe

rlit

er)/

(ml3

4.19

98)

ED

TA

,et

hyle

nedi

amin

ete

tra

acet

icac

id.

a Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

535

Table V. Indicators for Analyses

Alizarin 1.0 g sodium alizarin sulfonate, 1,000 ml H2O.Bromocresol Green 0.4 g bromocresol green, 1,000 ml H2O, 0.5 ml 1.0 N NaOH.Bromocresol Purple 0.4 g bromocresol purple, 1,000 ml H2O, 1.0 ml 1.0 N NaOH.EBT Powder 2.0 g Eriochrome Black T, 198 g NaCl.EBT Solution 5.0 g Eriochrome Black T, 150 ml methanol, 100 ml triethanolamine.FAS 50 g ferrous ammonium sulfate, 950 ml H2O, 10 ml conc. HNO3.K2CrO4 20 g K2CrO4, 980 ml H2O.Methyl Orange 1.0 g methyl orange (sodium salt), 1,000 ml H2O.Murexide 2.0 g murexide, 198 g NaCl.PAN 1.0 g peroxyacetal nitrate, 1,000 ml methanol.Phenolphthalein 1.0 g phenolphthalein, 500 ml ethanol, 500 ml H2O.Starch Solution 10.0 g starch, 1,000 ml hot H2O, 0.5 ml formaldehyde.Sulfo Orange 100 ml sulfo orange, 100 g NaCN, 845 ml H2O.

Note: Use deionized or distilled water for preparation of all solutions.

Table VI. Reagents for Analyses

Ammonium Oxalate Solution 40 g ammonium oxalate, 960 ml H2O.Dimethylglyoxime Solution 10 g dimethylglyoxime, 1,000 ml ethanol.Fluoride Buffer Dissolve 40 g monochloroacetic acid in 400 ml H2O and divide the

solution in two equal parts. Add phenolphthalein to one part andtitrate with 1.0 N NaOH from colorless to pink. Mix both partsand add H2O to 1,000 ml.

KF Solution 100 g KF dissolved in 1,000 ml H2O. Neutralize to pH 7.0 with1.0 N NaOH.

NaCN Solution 100 g NaCN, 900 ml H2O.Na2SO4 Solution 135 g Na2SO4, 950 ml H2O.pH 10 Buffer 350 ml conc. NH4OH, 54 g NH4Cl, 625 ml H2O.Reducing Solution 100 ml conc. HCl, 250 ml conc. HC2H3O2, 200 ml ethanol,

450 ml H2O.Rochelle Solution 200 g Rochelle salts, 800 ml H2O.SbCl3 Solution 2.0 g SbCl3, 100 ml 50% HCl.Silver Nitrate Solution 10 g AgNO3, 95 ml H2O.Sodium Sulfite Solution 100 g sodium sulfite, 950 ml H2O. Adjust to pH 9.0 with 1.0 N

NaOH or 1.0 N HCl. Solution has a 1-week shelf life.Tartaric Acid Solution 150 g tartaric acid, 950 ml H2O.

Note: Use deionized or distilled water for preparation of all reagents.

Table VII. Properties of Reagent Grade Acids

Acid Formula Wt % Specific Gravity (60˚F) Pounds/Gallon

Acetic HC2H3O2 99.0 1.050 8.76Fluoboric HBF4 48.0 1.365 11.38Formic HCHO2 98.0 1.220 10.17Hydrobromic HBr 48.0 1.490 12.43Hydrochloric HCl 36.0 1.183 9.87Hydrofluoric HF 70.0 1.256 10.48Nitric HNO3 70.0 1.420 11.84Phosphoric H3PO4 85.0 1.690 14.09Sulfuric H2SO4 93.0 1.835 15.30

536

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Bra

ssC

uCN

(Met

hod

I)2

ml

15m

lcon

c.H

NO 3,

heat

tobl

ueco

lor,

100

mlH

2O

,aco

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

,an

dad

dP

AN

.

0.1

ME

DT

AP

urpl

e-gr

een

CuC

N(o

z/ga

l)52.

985

3M

3[2

3C

uCN

ml2

0.8

3Z

n(C

N) 2

ml]

CuC

N(M

etho

dII)

2m

l10

0m

lH2O

,15

mlc

onc.

HN

O 3,

heat

tobl

ueco

lor

and

disa

ppea

ranc

eof

brow

nfu

mes

,N

H 4O

Hto

deep

blue

,ac

etic

acid

tolig

htbl

ue,

5g

KI.

Titr

ate

with

Na 2

S 2O

3to

pale

yello

w,

add

5m

lsta

rch

solu

tion,

cont

inue

titra

ting

toco

lorle

ss.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

uCN

(oz/

gal)5

ml3

5.97

13

N

Zn(

CN

) 25

ml

100

mlH

2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eZ

n(C

N) 2(o

z/ga

l)5

ml3

3.13

13

M

NaC

Nor

5m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dN

aCN

(oz/

gal)5

ml3

2.61

43

NK

CN

KC

N(o

z/ga

l)5

ml3

3.47

33

N

NaO

Hor

5m

l25

mlH

2O

and

5m

lsul

fo-o

rang

e.1.

0N

HC

lO

rang

e-ye

llow

NaO

H(o

z/ga

l)5

ml3

1.06

73

NK

OH

KO

H(o

z/ga

l)5

ml3

1.49

63

N

Na 2

CO

3or

10m

l10

0m

lhot

H 2O

,35

ml1

0%B

a(N

O 3) 2

,al

low

tose

ttle,

filte

r,w

ash

filte

rtw

ice

with

hot

H2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

,an

dm

ethy

lora

nge.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

K2C

O3

K2C

O3

(oz/

gal)

5m

l30.

921

3N

537

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

KN

aC4H

4O

6·4

H2O

5m

l25

ml2

0%H 2

SO

4,

filte

r,w

ash

flask

and

filte

rpa

per

twic

eea

chw

ithH 2O

,an

dbo

ilth

eco

llect

edfil

trat

e5

min

utes

.

0.1

NK

MnO

4C

olor

less

-pin

kK

NaC

4H

4O

6·4

H2O

(oz/

gal)

5m

l31.

250

3N

Bro

nze

Cu

(Met

hod

I)2

ml

15m

lcon

c.H

NO 3,

heat

tobl

ueco

lor,

100

mlH

2O

,co

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

and

add

PA

N.

0.1

ME

DT

AP

urpl

e-gr

een

Cu

(oz/

gal)5

ml3

4.23

63

M

Cu

(Met

hod

II)2

ml

100

mlH

2O

,15

mlc

onc.

HN

O 3,

heat

tobl

ueco

lor

and

disa

ppea

ranc

eof

brow

nfu

mes

,N

H 4O

Hto

deep

blue

,ac

etic

acid

tolig

htbl

ue,

5g

KI.

Titr

ate

with

Na 2

S 2O

3to

pale

yello

w,

add

5m

lsta

rch

solu

tion,

cont

inue

titra

ting

toco

lorle

ss.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

u(o

z/ga

l)5m

l34.

236

3N

Sn

5m

l10

0m

lH2O

,50

mlc

onc.

HC

l,3.

0g

iron

pow

der

in50

0-m

lfla

sk.

Sto

pper

flask

with

stop

per

fitte

dw

itha

glas

stu

beim

mer

sed

ina

beak

erfil

led

with

satu

rate

dbi

carb

onat

eso

lutio

n.H

eat

gent

lytil

liro

ndi

ssol

ves.

Coo

lto

room

tem

pera

ture

,m

akin

gsu

reou

tlet

tube

isim

mer

sed

inbi

carb

onat

eso

lutio

n.A

dd10

mls

tarc

hso

lutio

nan

dbi

carb

onat

edu

ring

titra

tion.

0.1

NK

I-K

IO3

Cle

ar-b

lue

Sn

(oz/

gal)5

ml3

1.58

33

N

NaC

Nor

5m

l10

0m

lH2O

and

10m

l10K

I.0.

1N

AgN

O 3C

lear

-tur

bid

NaC

N(o

z/ga

l)5m

l32.

614

3N

KC

NK

CN

(oz/

gal)

5m

l33.

473

3N

NaO

Hor

5m

l25

mlH

2O

and

5m

lsul

fo-o

rang

e.1.

0N

HC

lO

rang

e-ye

llow

NaO

H(o

z/ga

l)5

ml3

1.06

73

NK

OH

KO

H(o

z/ga

l)5

ml3

1.49

63

N

538

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Na 2

CO

3or

K2C

O3

10m

l10

0m

lhot

H 2O

,35

ml1

0%B

a(N

O 3) 2

,al

low

tose

ttle,

filte

r,w

ash

filte

rtw

ice

with

hot

H2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

and

met

hylo

rang

e.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

K2C

O3

(oz/

gal)

5m

l30.

921

3N

KN

aC4H

4O

6·4

H2O

5m

l25

ml2

0%H 2

SO

4,

filte

r,w

ash

flask

and

filte

rpa

per

twic

eea

chw

ithH 2O

,an

dbo

ilth

eco

llect

edfil

trat

e5

min

utes

.

0.1

NK

MnO

4C

olor

less

-pin

kK

NaC

4H

4O

6·4

H2O

(oz/

gal)

5m

l31.

250

3N

Ca

dm

ium

Cya

nid

eC

d2

ml

100

mlH

2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eC

d(o

z/ga

l)5m

l37.

493

3M

Tot

alan

d5

ml

100

mlH

2O

,15

mlc

onc.

NH 4

OH

,an

d10

ml1

0%K

I.0.

1N

AgN

O3

Cle

ar-t

urbi

dT

otal

NaC

N(o

z/ga

l)5m

l32.

614

3N

Fre

eN

aCN

Fre

eN

aCN

(oz/

gal)5

Tot

alN

aCN

21.

744

3C

dN

aOH

5m

l25

mlH

2O

and

5m

lsul

fo-o

rang

e.1.

0N

HC

lO

rang

e-ye

llow

NaO

H(o

z/ga

l)5

ml3

1.06

73

N

Na 2

CO

310

ml

100

mlh

otH 2

O,

35m

l10%

Ba(

NO 3

) 2,

allo

wto

settl

e,fil

ter,

was

hfil

ter

twic

ew

ithho

tH

2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

and

met

hylo

rang

e.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

Ca

dm

ium

Flu

ob

ora

teC

d2

ml

100

mlH

2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eC

d(o

z/ga

l)5m

l37.

493

3M

539

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

NH

4B

F 45

ml

50m

lH2O

,bo

iling

chip

s,50

ml2

0%N

aOH

inK

jeld

ahlf

lask

.A

ttach

flask

toth

edi

still

atio

nap

para

tus

with

the

colle

ctio

ntu

befr

omth

eco

nden

ser

imm

erse

din

abe

aker

cont

aini

ng10

0m

lsa

tura

ted

H 3BO

3so

lutio

n.B

oilf

lask

till

20m

lrem

ain

inst

ill.

Rem

ove

beak

eran

dad

dm

ethy

lora

nge.

0.1

NH

Cl

Yel

low

-red

NH 4

BF 4

(oz/

gal)

5m

l32.

795

3N

Ca

dm

ium

Su

lfate

Cd

2m

l10

0m

lH2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eC

d(o

z/ga

l)5m

l37.

493

3M

H2S

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

100%

H2S

O4

(oz/

gal)

5m

l30.

654

3N

Ch

rom

ium

CrO

3(C

r61

)10

mlo

fst

ock

10-m

lsam

ple

into

500-

mlv

olum

etric

flask

.P

ipet

te10

mlo

fst

ock,

add

100

ml

H2O

,2

gam

mon

ium

biflu

orid

e,15

ml

conc

.H

Cl,

10m

l10%

KI,

and

star

chso

lutio

n.(S

eeT

able

XIII

for

alte

rnat

em

etho

ds.)

0.1

NN

a 2S 2

O3

Blu

eto

colo

rless

CrO 3

(oz/

gal)

5m

l322

.219

3N

Cr3

110

mlo

fst

ock

10-m

lsam

ple

into

500

mlv

olum

etric

.P

ipet

te10

mlo

fst

ock,

add

200

mlH 2

O,

0.25

gN

a 2O

2,

boil

gent

ly30

min

utes

,m

aint

ain

volu

me

at20

0m

lwith

H 2O.

Coo

l,ad

d2

gam

mon

ium

biflu

orid

e,15

mlc

onc.

HC

l,10

ml1

0%K

I,an

dst

arch

solu

tion.

0.1

NN

a 2S 2

O3

Blu

eto

colo

rless

Cr31

(oz/

gal)

5(m

l322

.219

3N

2C

r61

)3

0.52

0

540

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

SO

425

ml

100

mlH

2O

,10

0m

lred

ucin

gso

lutio

n,bo

il30

min

utes

,re

mov

efr

omhe

at,

add

50m

l10%

Ba(

NO 3

) 2,

100

mlh

otH 2

O.

Allo

wso

lutio

nto

stan

dfo

r3–

4ho

urs,

heat

solu

tion

tobo

iling

.F

ilter

inta

red

Goo

chcr

ucib

le,

was

hpr

ecip

itate

with

hot

H2O

,dr

yin

oven

at11

0˚C

,co

olin

desi

ccat

oran

dw

eigh

.

SO

4(o

z/ga

l)5

(wei

ght

ingr

ams

ofpr

ecip

itate

)32.

195

F5

ml

100

mlH

2O

,1.

0N

NaO

Hto

pH7.

5,us

ing

apH

met

erpr

evio

usly

stan

dard

ized

topH

7.0.

Add

10%

AgN

O 3so

lutio

nun

tilth

edi

sapp

eara

nce

ofth

eye

llow

colo

raf

ter

settl

ing

ofth

epr

ecip

itate

,fil

ter,

was

hpr

ecip

itate

,sa

vefil

trat

e.A

ddA

lizar

inin

dica

tor,

2%H

NO 3

tillc

olor

ofso

lutio

nch

ange

sfr

ompi

nkto

yello

w.

Add

3m

lflu

orid

ebu

ffer.

0.1

NT

h(N

O 3) 4

Yel

low

-pin

kF

(oz/

gal)5

ml3

0.50

73

N

Co

pp

er

Cya

nid

eC

uCN

(Met

hod

I)2

ml

15m

lcon

c.H

NO 3,

heat

tobl

ueco

lor,

100

mlH

2O

,co

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

,an

dad

dP

AN

.

0.1

ME

DT

AP

urpl

e-gr

een

CuC

N(o

z/ga

l)5m

l35.

971

3M

CuC

N(M

etho

dII)

2m

l10

0m

lH2O

,15

mlc

onc.

HN

O 3,

heat

tobl

ueco

lor

and

disa

ppea

ranc

eof

brow

nfu

mes

,N

H 4O

Hto

deep

blue

,ac

etic

acid

tolig

htbl

ue,

5g

KI.

Titr

ate

with

Na 2

S 2O

3to

pale

yello

w,

add

5m

lsta

rch

solu

tion,

cont

inue

titra

ting

toco

lorle

ss.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

uCN

(oz/

gal)5

ml3

5.97

13

N

541

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

NaC

Nor

5m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dN

aCN

(oz/

gal)5

ml3

2.61

43

NK

CN

KC

N(o

z/ga

l)5

ml3

3.47

33

N

NaO

Hor

5m

l25

mlH

2O

and

5m

lsul

fo-o

rang

e.1.

0N

HC

lO

rang

e-ye

llow

NaO

H(o

z/ga

l)5

ml3

1.06

73

NK

OH

KO

H(o

z/ga

l)5

ml3

1.49

63

N

Na 2

CO

3or

K2C

O3

10m

l10

0m

lhot

H 2O

,35

ml1

0%B

a(N

O 3) 2

,al

low

tose

ttle,

filte

r,w

ash

filte

rtw

ice

with

hot

H2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

,an

dm

ethy

lora

nge.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

K2C

O3,

etc

K2C

O3

(oz/

gal)

5m

l30.

921

3N

KN

aC4H

4O

6·4

H2O

5m

l25

ml2

0%H 2

SO

4,

filte

r,w

ash

flask

and

filte

rpa

per

twic

eea

chw

ithH 2O

,an

dbo

ilth

eco

llect

edfil

trat

e5

min

utes

.

0.1

NK

MnO

4C

olor

less

-pin

kK

NaC

4H

4O

6·4

H2O

(oz/

gal)

5m

l31.

250

3N

Co

pp

er

Flu

ob

ora

teC

u(M

etho

dI)

2m

l10

0m

lH2O

,co

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

,an

dad

dP

AN

.0.

1M

ED

TA

Pur

ple-

gree

nC

u(o

z/ga

l)5m

l34.

236

3M

Cu(

BF 4

) 2(o

z/ga

l)5

Cu

33.

73

Cu

(Met

hod

II)2

ml

100

mlH

2O

,N

H4O

Hto

deep

blue

,ac

etic

acid

tolig

htbl

ue,5

gK

I.T

itrat

ew

ithN

a 2S 2

O3

topa

leye

llow

,ad

d5

ml

star

chso

lutio

n,co

ntin

uetit

ratin

gto

colo

rless

.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

u(o

z/ga

l)5m

l34.

236

3N

HB

F 410

ml

100

mlH

2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-g

reen

100%

HB

F4

(oz/

gal)

5m

l31.

171

3N

Co

pp

er

Pyr

op

ho

sph

ate

Cu

(Met

hod

I)2

ml

100

mlH

2O

conc

.N

H 4O

Hto

deep

blue

,he

atto

140˚

Fan

dad

dP

AN

.0.

1M

ED

TA

Pur

ple-

gree

nC

u(o

z/ga

l)5m

l34.

236

3M

542

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Cu

(Met

hod

II)2

ml

100

mlH

2O

,N

H4O

Hto

deep

blue

,ac

e-tic

acid

tolig

htbl

ue,

5g

KI.

Titr

ate

with

Na 2

S 2O

3to

pale

yello

w,

add

5m

lsta

rch

solu

tion,

cont

inue

titra

ting

toco

lorle

ss.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

u(o

z/ga

l)5m

l34.

236

3N

Tot

alP 2

O7

5m

l10

0m

lH2O

,1.

0N

HC

ldro

pwis

eto

pH3.

8(u

sepH

met

erst

anda

rdiz

edat

pH4.

0),

back

-titr

ate

with

1.0

NN

aOH

ifpH

3.8

isov

ersh

ot,

stir

5m

inut

esan

dm

ake

sure

pHis

3.6–

3.8,

add

50m

l20%

ZnS

O 4(a

djus

ted

topH

3.8)

and

stir

10m

inut

es.

Titr

ate

slow

lyw

ithst

irrin

gus

ing

1.0

NN

aOH

topH

3.8

(not

eth

ese

mlN

aOH

used

for

calc

ulat

ion)

.

1.0

NN

aOH

Tot

alP 2O

7(o

z/ga

l)5

ml3

2.32

3N

1C

u3

1.37

Rat

io5

[Tot

alP 2

O7

(oz/

gal)]

/Cu

(oz/

gal)

NH

310

ml

200

mlH

2O

,bo

iling

chip

s,50

ml2

0%N

aOH

inK

jeld

ahlf

lask

.A

ttach

flask

toth

edi

still

atio

nap

para

tus

with

the

colle

ctio

ntu

befr

omth

eco

nden

ser

imm

erse

din

abe

aker

cont

aini

ng10

0m

lsa

tura

ted

H 3BO

3so

lutio

n.B

oilf

lask

and

dist

illov

er10

0m

l.R

emov

ebe

aker

and

add

met

hylo

rang

e.

0.1

NH

Cl

Yel

low

-red

29%

NH 3

(oz/

gal)

5m

l30.

803

N

Co

pp

er

Su

lfate

Cu

(Met

hod

I)2

ml

100

mlH

2O

,co

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

,an

dad

dP

AN

.0.

1M

ED

TA

Pur

ple-

gree

nC

u(o

z/ga

l)5m

l34.

236

3M

CuS

O 4·5

H2O

(oz/

gal)

5C

u3

3.93

Cu

(Met

hod

II)2

ml

100

mlH

2O

,N

H4O

Hto

deep

blue

,ac

etic

acid

tolig

htbl

ue,5

gK

I.T

itrat

ew

ithN

a 2S 2

O3

topa

leye

llow

,ad

d5

ml

star

chso

lutio

n,co

ntin

uetit

ratin

gto

colo

rless

.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

u(o

z/ga

l)5m

l34.

236

3N

543

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Cu

(Met

hod

III)

(See

Tab

leX

IV)

H2S

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-g

reen

100%

H2S

O4

(oz/

gal)

5m

l30.

654

3N

Cl

50m

l50

mlH

2O

,25

ml5

0%H

NO 3

,5

drop

s0.

1N

AgN

O3.

Not

e:F

orch

lorid

ean

alys

is,

carb

on-t

reat

the

solu

tion

prio

rto

anal

ysis

.

0.01

NH

g(N

O 3) 2

Tur

bid-

clea

rC

l(pp

m)5

ml3

709.

13

N

Aci

dG

old

Au

20m

l25

mlc

onc.

H 2S

O4,

heat

tow

hite

fum

es,

cool

,ad

d10

ml3

0%H 2O

2,

heat

tow

hite

fum

es.

Rep

eat

H 2O2

and

heat

ing

until

Au

spon

geco

agul

ates

and

solu

tion

clea

rs.

Coo

l,ad

d10

0m

lH2O

,he

atat

140˚

Ffo

r5

min

utes

.F

ilter

thro

ugh

Goo

chcr

ucib

leco

ntai

ning

fiber

glas

sfil

ter

pape

r,w

ash

Au

spon

gew

ithho

tH 2O

,dr

ycr

ucib

lein

oven

at11

0˚C

,co

olin

desi

ccat

oran

dw

eigh

.

Au

(g/L

)5

(wei

ght

ofgo

ldpr

ecip

itate

)350

.0

Go

ldC

yan

ide

Au

20m

lP

roce

dure

asab

ove

for

acid

gold

.A

sab

ove

for

acid

gold

.

NaC

Nor

5m

l10

0m

lH2O

,10

ml1

0%K

I.0.

1N

AgN

O 3C

lear

-tur

bid

NaC

N(g

/L)5

ml3

19.6

053

NK

CN

KC

N(g

/L)

5m

l326

.048

3N

Na 2

CO

3or

K2C

O3

10m

l10

0m

lhot

H 2O

,35

ml1

0%B

a(N

O 3) 2

,al

low

tose

ttle,

filte

r,w

ash

filte

rtw

ice

with

hot

H2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

,an

dm

ethy

lora

nge.

1.0

NH

Cl

Ora

nge-

pink

NaC

O 3(g

/L)

5m

l35.

303

3N

K2C

O3

(g/L

)1

ml3

6.90

83

N

544

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Ind

ium

Cya

nid

eIn

2m

l10

0m

lH2O

,50

mlR

oche

lleso

lutio

n,10

mlp

H10

buffe

r,he

atto

140˚

F,

and

add

EB

Tpo

wde

r.

0.1

ME

DT

AR

ed-b

lue

In(o

z/ga

l)5m

l37.

655

3M

Tot

alK

CN

5m

l10

0m

lH2O

,20

ml2

0%N

aOH

,an

d10

ml1

0%K

I.0.

1N

AgN

O3

Cle

ar-t

urbi

dT

otal

KC

N(o

z/ga

l)5m

l33.

473

3N

Fre

eK

CN

5m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dF

ree

KC

N(o

z/ga

l)5m

l33.

473

3N

KO

H5

ml

25m

lH2O

and

5m

lsul

fo-o

rang

e.1.

0N

HC

lO

rang

e-ye

llow

KO

H(o

z/ga

l)5

ml3

1.49

63

N

Ind

ium

Flu

ob

ora

teIn

2m

l10

0m

lH2O

,50

mlR

oche

lleso

lutio

n,10

mlp

H10

buffe

r,he

atto

140˚

F,

and

add

EB

Tpo

wde

r.

0.1

ME

DT

AR

ed-b

lue

In(o

z/ga

l)5m

l37.

655

3M

NH

4B

F 45

ml

50m

lH2O

,bo

iling

chip

s,50

ml2

0%N

aOH

inK

jeld

ahlf

lask

.A

ttach

flask

toth

edi

still

atio

nap

para

tus

with

the

colle

ctio

ntu

befr

omth

eco

nden

ser

imm

erse

din

abe

aker

cont

aini

ng10

0m

lsa

tura

ted

H 3BO

3so

lutio

n.B

oilf

lask

till

20m

lrem

ain

inst

ill.

Rem

ove

beak

eran

dad

dm

ethy

lora

nge.

0.1

NH

Cl

Yel

low

-red

NH 4

BF 4

(oz/

gal)

5m

l32.

795

3N

Iro

nC

hlo

rid

eF

e21

5m

l10

0m

lH2O

,25

ml2

0%Z

nSO 4

,an

d50

ml1

0%H 2

SO

4.

0.1

NK

MnO

4C

olor

less

-pin

kF

e21

(oz/

gal)

5m

l31.

489

3N

545

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Tot

alF

e5

ml

100

mlH

2O

,5

gC

dfla

kes,

boil

5m

inut

es,

cool

and

deca

ntliq

uid

into

500-

mlf

lask

,w

ash

Cd

resi

due

with

H2O

and

add

tofla

sk,

add

25m

l20%

ZnS

O4,

and

50m

l10%

H 2S

O4.

0.1

KM

NO

4C

olor

less

-pin

kT

otal

Fe

(oz/

gal)5

ml3

1.48

93

NF

e31

(oz/

gal)

5T

otal

Fe

2F

e21

HC

l25

ml

100

mlH

2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

36%

HC

l(oz

/gal

)5

ml3

0.54

03

N

Iro

nF

luo

bo

rate

Fe2

15

ml

100

mlH

2O

,25

ml2

0%Z

nSO 4

,an

d50

ml1

0%H 2

SO

4.

0.1

KM

nO4

Col

orle

ss-p

ink

Fe21

(oz/

gal)

5m

l31.

489

3N

Tot

alF

e5

ml

100

mlH

2O

,5

gC

dfla

kes,

boil

5m

inut

es,

cool

and

deca

ntliq

uid

into

500-

mlf

lask

,w

ash

Cd

resi

due

with

H2O

and

add

tofla

sk,

add

25m

l20%

ZnS

O4,

and

50m

l10%

H 2S

O4.

0.1

NK

MnO

4C

olor

less

-pin

kT

otal

Fe

(oz/

gal)5

ml3

1.48

93

N

Fe3

1(o

z/ga

l)5

Tot

alF

e2

Fe2

1

NaC

l5

ml

100

mlH

2O

,5

ml3

0%H 2

O2,

boil

for

10m

inut

es,

filte

r,w

ash

prec

ipita

tew

ithho

tH

2O

,an

dad

dK 2

CrO

4to

filtr

ate.

0.1

NA

gNO

3Y

ello

w-r

edN

aCl(

oz/g

al)5

ml3

1.55

83

N

Le

ad

Flu

ob

ora

teP

b1

ml

100

mlH

2O

,25

mlR

oche

lleso

lutio

n,20

mlc

onc.

NH 4

OH

,an

dE

BT

solu

tion.

0.1

ME

DT

AR

ed-b

lue

Pb

(oz/

gal)5

ml3

27.6

253

M

HB

F 410

ml

100

mlH

2O

.1.

0N

NaO

HC

lear

-tur

bid

100%

HB

F4

(oz/

gal)

5m

l31.

171

3N

Bla

ckN

icke

lZ

n2

ml

100

mlH

2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eZ

n(o

z/ga

l)5m

l34.

358

3M

546

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Ni

2m

l10

0m

lH2O

,10

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

(mlE

DT

Afo

rN

i2

ml

ED

TA

for

Zn)

33.

914

3M

NaS

CN

10m

l10

0m

lH2O

,15

ml2

0%H 2

SO

4,

and

FA

Sin

dica

tor.

0.1

NA

gNO

3R

ed-c

olor

less

NaS

CN

(oz/

gal)5

ml3

1.08

13

N

Nic

kelF

luo

bo

rate

Ni

2m

l10

0m

lH2O

,10

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

H3B

O3

10m

l25

mlH

2O

,5.

0g

man

nito

l,an

dbr

omoc

reso

lpur

ple.

1.0

NN

aOH

Gre

en-p

urpl

eH 3B

O3

(oz/

gal)

5m

l30.

824

3N

Nic

kelS

trik

eN

i2

ml

100

mlH

2O

,20

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

HC

l10

ml

100

mlH

2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

36%

HC

l(fl

oz/g

al)

5m

l31.

115

3N

Nic

kelS

ulfa

ma

teN

i2

ml

100

mlH

2O

,20

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

NiB

r 25

ml

100

mlH

2O

and

K 2C

rO4.

0.1

NA

gNO 3

Yel

low

/gre

en-r

edN

iBr 2

(oz/

gal)

5m

l32.

914

3N

NiC

l 2·6

H2O

20m

l10

0m

lH2O

and

K 2C

rO4.

0.1

NA

gNO 3

Yel

low

/gre

en-r

edN

iCl 2·6H

2O

(oz/

gal)

5m

l30.

792

3N

H3B

O3

10m

l25

mlH

2O

,5.

0g

man

nito

l,an

dbr

omoc

reso

lpur

ple.

1.0

NN

aOH

Gre

en-p

urpl

eH 3B

O3

(oz/

gal)

5m

l30.

824

3N

547

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

SO

410

ml

100

mlH

2O

,5

ml5

0%H

Cl,

25m

lB

a(N

O3) 2

,al

low

solu

tion

tost

and

4ho

urs,

filte

rin

tare

dG

ooch

cruc

ible

,w

ash

prec

ipita

tew

ithH 2O

,dr

yin

oven

at11

0˚C

,co

olin

desi

ccat

or,

and

wei

gh.

SO

4(o

z/ga

l)5

(wei

ght

ingr

ams

ofpr

ecip

itate

)35.

488

Wa

tts

Nic

kel

Ni

2m

l10

0m

lH2O

,20

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

NiC

l 2·6

H2O

1m

l10

0m

lH2O

,1

mlK

2C

rO4

(ifpH

isbe

low

4.0,

add

1.0

gC

aCO 3).

0.1

NA

gNO

3Y

ello

w/g

reen

-red

NiC

l 2·6

H2O

(oz/

gal)5

ml3

15.8

473

N

NiS

O4·6

H2O

(oz/

gal)

54.

5(N

i20.

247

3N

iCl 2

·6H

2O

)

H3B

O3

10m

l25

mlH

2O

,5.

0g

man

nito

l,an

dbr

omoc

reso

lpur

ple.

1.0

NN

aOH

Gre

en-p

urpl

eH 3B

O3

(oz/

gal)

5m

l30.

824

3N

Nic

kel-Ir

on

Ni

2m

l10

0m

lH2O

,20

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

Fe2

15

ml

100

mlH

2O

,25

ml2

0%Z

nSO 4

,an

d50

ml1

0%H 2

SO

4.

0.1

NK

MnO

4C

olor

less

-pin

kF

e21

(oz/

gal)

5m

l31.

489

3N

Tot

alF

e5

ml

100

mlH

2O

,5

gC

dfla

kes,

boil

5m

inut

es,

cool

and

deca

ntliq

uid

into

500-

mlf

lask

,w

ash

Cd

resi

due

with

H2O

and

add

tofla

sk,

add

25m

l20%

ZnS

O4,

and

50m

l10%

H 2S

O4.

0.1

KM

NO

4C

olor

less

-pin

kT

otal

Fe

(oz/

gal)5

ml3

1.48

93

NF

e31

(oz/

gal)

5T

otal

Fe

2F

e21

H3B

O3

10m

l25

mlH

2O

,5.

0g

man

nito

l,an

dbr

omoc

reso

lpur

ple.

1.0

NN

aOH

Gre

en-p

urpl

eH 3B

O3

(oz/

gal)

5m

l30.

824

3N

548

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Pa

llad

ium

Pd

10m

l10

mlc

onc.

HN

O 3,he

atun

tilsy

rupy

,10

mlc

onc.

HN

O 3,

heat

toon

set

ofbo

iling

.A

dd25

0m

lH2O

,co

ol,

slow

lyad

d40

mld

imet

hylg

lyox

ime

solu

tion,

allo

wso

lutio

nto

stan

dat

leas

t2

hour

s,fil

ter

thro

ugh

No.

3po

rosi

tyta

red

cruc

ible

,w

ash

prec

ipita

tew

ithH 2O

.D

ryin

oven

at11

0˚C

,co

olin

desi

ccat

or,

and

wei

gh.

Pd

(g/L

)5(w

eigh

tin

gram

sof

prec

ipita

te)3

31.6

7

Pla

tinu

mP

t10

ml

10m

lcon

c.H

Cl,

heat

until

syru

py,

100

mlH

2O

,5

gso

dium

acet

ate,

1m

lcon

c.fo

rmic

acid

,he

atat

140˚

Ffo

r5

hour

s,fil

ter,

was

hpr

ecip

itate

with

hot

H 2O.

Pla

cefil

ter

pape

ran

dP

tpr

ecip

itate

inta

red

porc

elai

ncr

ucib

le,

dry

slow

lyw

ithB

unse

nbu

rner

,ch

arfil

ter

pape

r,dr

yP

tpr

ecip

itate

athi

ghte

mpe

ratu

refo

r30

min

utes

.C

ooli

nde

sicc

ator

and

wei

gh.

Pt

(g/L

)5(w

eigh

tin

gram

sof

prec

ipita

te)3

100.

0

Rh

od

ium

Rh

25m

l2

gM

gtu

rnin

gs,

conc

.H

Cld

ropw

ise.

Whe

nal

lMg

diss

olve

s,ad

d0.

5g

Mg

turn

ings

and

HC

ldro

pwis

eto

ensu

reco

mpl

ete

prec

ipita

tion

ofR

h.F

ilter

solu

tion

inta

red

Goo

chcr

ucib

leco

ntai

ning

fiber

glas

sfil

ter

pape

r,w

ash

prec

ipita

tew

ithho

tH 2

O,

dry

inov

enat

110˚

C,

cool

inde

sicc

ator

and

wei

gh.

Rh

(g/L

)5(w

eigh

tin

gram

sof

prec

ipita

te)3

40.0

H2S

O4

or

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

100%

H2S

O4

(g/L

)5

ml3

4.90

43

NH

3P

O4

100%

H 3P

O4

(g/L

)5

ml3

9.80

03

N

549

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Ru

the

niu

mR

uthe

nium

cann

otbe

easi

lyde

term

ined

byvo

lum

etric

orgr

avim

etric

met

hods

.It

isus

ually

dete

rmin

edby

emis

sion

spec

tros

copy

and

itsan

alys

issh

ould

bere

ferr

edto

aco

mpe

tent

labo

rato

ry.

Silv

er

Cya

nid

eA

g5

ml

15m

lcon

c.H 2

SO

4,

5m

lcon

c.H

NO 3

,he

atun

tilth

edi

sapp

eara

nce

ofor

ange

fum

es,

cool

,ad

d10

0m

lcol

dH 2O

,an

dF

AS

indi

cato

r.

0.1

NK

SC

NC

olor

less

-red

Ag

(oz/

gal)5

ml3

2.87

73

NA

gCN

(oz/

gal)

5A

g3

1.24

1

NaC

Nor

5m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dN

aCN

(oz/

gal)5

ml3

2.61

43

NK

CN

KC

N(o

z/ga

l)5

ml3

3.47

33

N

Na 2

CO

3or

10m

l10

0m

lhot

H 2O

,35

ml1

0%B

a(N

O 3) 2

allo

wto

settl

e,fil

ter,

was

hfil

ter

twic

ew

ithho

tH

2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

and

met

hylo

rang

e.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

K2C

O3

K2C

O3

(oz/

gal)

5m

l30.

921

3N

Tin

Flu

ob

ora

teS

n21

2m

l10

0m

lH2O

,25

ml5

0%H

Cl,

10m

lst

arch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

Sn21

(oz/

gal)

5m

l33.

956

3N

550

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Sn4

12

ml

In50

0-m

lfla

skad

dsa

mpl

e,10

0m

lco

nc.

HC

l,2

drop

sS

bCl

3so

lutio

n.A

dd18

0m

lH2O

,5-

in.

fold

ed“U

”-sh

aped

nick

elst

ripan

d5.

0g

redu

ced

iron

pow

der.

Sto

pper

flask

with

rubb

erst

oppe

rfit

ted

with

1⁄4-

in.

glas

stu

beim

mer

sed

into

asa

tura

ted

NaH

CO

3

solu

tion.

Hea

tso

lutio

non

hot

plat

eto

boil

for

20m

inut

esan

dth

enpl

ace

inco

olin

gta

nkan

dal

low

toco

olto

room

tem

pera

ture

.M

ake

sure

glas

sou

tlet

tube

isim

mer

sed

inth

eN

aHC

O 3.R

emov

est

oppe

ran

dad

dst

arch

solu

tion.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

Sn41

(oz/

gal)

5m

l33.

956

3N

2S

n21

HB

F 410

ml

100

mlH

2O

and

met

hylo

rang

e.1.

0N

NaO

HC

lear

-tur

bid

100%

HB

F4

(oz/

gal)

5m

l31.

171

3N

Fre

eH 3

BO

310

ml

100

mlH

2O

,10

mlN

a 2S

O4

solu

tion.

Titr

ate

topH

7.0,

usin

ga

pHm

eter

prev

ious

lyst

anda

rdiz

edto

pH7.

0.A

dd5

gm

anni

tol,

titra

tefr

ompH

7.0

topH

8.0

(mlN

aOH

requ

ired

for

this

step

are

used

for

the

calc

ulat

ion)

.

1.0

NN

aOH

H 3B

O3

(oz/

gal)

5m

l30.

824

3N

551

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Tin

Sta

nn

ate

K2S

nO3·3

H2O

5m

l10

0m

lH2O

,50

mlc

onc.

HC

l,3.

0g

iron

pow

der

in50

0-m

lfla

sk.

Sto

pper

flask

with

stop

per

fitte

dw

itha

glas

stu

beim

mer

sed

ina

beak

erfil

led

with

satu

rate

dbi

carb

onat

eso

lutio

n.H

eat

gent

lytil

liro

ndi

ssol

ves.

Coo

lto

room

tem

pera

ture

,m

akin

gsu

reou

tlet

tube

isim

mer

sed

inbi

carb

onat

eso

lutio

n.A

dd10

mls

tarc

hso

lutio

nan

dbi

carb

onat

edu

ring

titra

tion.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

K 2SnO

3·3

H2O

(oz/

gal)5

ml3

3.98

63

NN

a 2S

nO3·3

H2O

Na 2

SnO

3·3

H2O

(oz/

gal)

5m

l33.

556

3N

KO

H5

ml

25m

lH2O

and

5m

lsul

fo-o

rang

e1.

0N

HC

lO

rang

e-ye

llow

KO

H(o

z/ga

l)5

ml3

1.49

63

NN

aOH

NaO

H(o

z/ga

l)5m

l31.

067

3N

Tin

Su

lfate

SnS

O 45

ml

100

mlH

2O

,25

ml5

0%H

Cl,

10m

lst

arch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

SnS

O 4(o

z/ga

l)5

ml3

2.86

33

NS

n21

(oz/

gal)

5S

nSO 4

30.

553

Sn4

12

ml

In50

0-m

lfla

skad

dsa

mpl

e,10

0m

lco

nc.

HC

l,2

drop

sS

bCl

3so

lutio

n.A

dd18

0m

lH2O

,5-

in.

fold

ed“U

”-sh

aped

nick

elst

ripan

d5.

0g

redu

ced

iron

pow

der.

Sto

pper

flask

with

rubb

erst

oppe

rfit

ted

with

1⁄4-

in.

glas

stu

beim

mer

sed

into

asa

tura

ted

NaH

CO

3

solu

tion.

Hea

tso

lutio

non

hot-

plat

eto

boil

for

20m

inut

esan

dth

enpl

ace

inco

olin

gta

nkan

dal

low

toco

olto

room

tem

pera

ture

.M

ake

sure

glas

sou

tlet

tube

isim

mer

sed

inth

eN

aHC

O 3.R

emov

est

oppe

ran

dad

dst

arch

solu

tion.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

Sn41

(oz/

gal)

5m

l33.

956

3N

2S

n21

552

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

H2S

O4

10m

l10

0m

lH2O

,25

mla

mm

oniu

mox

alat

eso

lutio

n,an

dm

ethy

lora

nge.

1.0

NN

aOH

Red

-or

ange

/yel

low

100%

H 2S

O4

(oz/

gal)

5m

l30.

654

%v

H2S

O4

5m

l30.

279

3N

Tin

-Le

ad

Flu

ob

ora

teS

n21

100

ml

H 2O

,25

ml5

0%H

Cl,

10m

lsta

rch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n0.

1N

KI-

KIO

3C

olor

less

-blu

eS

n21

(oz/

gal)

5m

l33.

956

3N

Sn4

12

ml

In50

0-m

lfla

skad

dsa

mpl

e,10

0m

lco

nc.

HC

l,2

drop

sS

bCl

3so

lutio

n.A

dd18

0m

lH2O

,5-

in.

fold

ed“U

”-sh

aped

nick

elst

ripan

d5.

0g

redu

ced

iron

pow

der.

Sto

pper

flask

with

rubb

erst

oppe

rfit

ted

with

1⁄4-

in.

glas

stu

beim

mer

sed

into

asa

tura

ted

NaH

CO

3

solu

tion.

Hea

tso

lutio

non

hot-

plat

eto

boil

for

20m

inut

esan

dth

enpl

ace

inco

olin

gta

nkan

dal

low

toco

olto

room

tem

pera

ture

.M

ake

sure

glas

sou

tlet

tube

isim

mer

sed

inth

eN

aHC

O 3.R

emov

est

oppe

ran

dad

dst

arch

solu

tion.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

Sn41

(oz/

gal)

5m

l33.

956

3N

2S

n21

Pb

2m

l5

mlc

onc.

HN

O 3,

heat

tills

yrup

y,co

olan

dad

d:25

mlR

oche

lleso

lutio

n,15

ml

conc

.N

H 4O

H,

15m

l10%

NaC

Nan

dE

BT

solu

tion.

0.1

ME

DT

AR

ed-b

lue

Pb

(oz/

gal)5

ml3

13.8

133

M

HB

F 410

ml

100

mlH

2O

.1.

0N

NaO

HC

lear

-tur

bid

100%

HB

F4

(oz/

gal)

5m

l31.

171

3N

553

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Fre

eH 3

BO

310

ml

100

mlH

2O

,10

mlN

a 2S

O4

solu

tion.

Titr

ate

topH

7.0,

usin

ga

pHm

eter

prev

ious

lyst

anda

rdiz

edto

pH7.

0.A

dd5

gm

anni

tol,

titra

tefr

ompH

7.0

topH

8.0

(mlN

aOH

requ

ired

for

this

step

are

used

for

the

calc

ulat

ion)

.

1.0

NN

aOH

H 3B

O3

(oz/

gal)

5m

l30.

824

3N

Tin

-Le

ad

Me

tha

ne

Su

lfon

ate

Sn1

25

ml

100

mlH

2O

,25

ml5

0%H

Cl,

10m

lst

arch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n.

0.1

NK

I-K

IO3

Col

orle

ssbl

ueS

n21

(g/L

)5

ml3

11.8

693

N

Sn4

15

ml

In50

0-m

lfla

skad

dsa

mpl

e,10

0m

lco

nc.

HC

l,2

drop

sS

bCl

3so

lutio

n.A

dd18

0m

lH2O

,fo

lded

“U”-

shap

edni

ckel

strip

and

5.0

gre

duce

diro

npo

wde

r.S

topp

erfla

skw

ithru

bber

stop

per

fitte

dw

ith1⁄4-

in.

glas

stu

beim

mer

sed

into

asa

tura

ted

NaH

CO 3

solu

tion.

Hea

tso

lutio

non

hot-

plat

eto

boil

for

20m

inut

esan

dth

enpl

ace

inco

olin

gta

nkan

dal

low

toco

olto

room

tem

pera

ture

.M

ake

sure

glas

sou

tlet

tube

isim

mer

sed

inth

eN

aHC

O 3.

Rem

ove

stop

per

and

add

star

chso

lutio

n.

0.1

NK

I-K

IO3

Col

orle

ss-b

lue

Sn41

(g/L

)5

ml3

11.8

693

N(S

n21

)

Pb

25m

l75

mlH

2O

,3

mlH

2O

2,

50m

lRoc

helle

solu

tion,

25m

lpH

10bu

ffer,

EB

Tso

lutio

n,15

ml1

0%fo

rmal

dehy

de.

0.1

ME

DT

AR

ed-b

lue

Pb

(g/L

)5m

l38.

288

3M

Met

hane

sulfo

nic

acid

(MS

A)

10m

l10

0m

lH2O

,ph

enol

phth

alei

n.1.

0N

NaO

HC

olor

less

-pin

k10

0%M

SA

(g/L

)5

ml3

9.61

3N

554

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Tin

-Nic

kel

Sn

2m

l10

0m

lH2O

,25

ml5

0%H

Cl,

10m

lst

arch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n.

0.1

NK

I-K

IO3

Cle

arbl

ueS

n(o

z/ga

l)5m

l33.

956

3N

Ni

2m

l25

mlH

2O

,1

ml3

0%H 2

O2,

heat

gent

lyto

boil,

cool

,ad

d10

mlt

arta

ricac

idso

lutio

n.N

eutr

aliz

ew

ithco

nc.

NH 4O

Hto

abl

ueco

lor,

add

20m

lpH

10bu

ffer,

150

mlH

2O

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

3.91

43

M

NH

4H

F 210

ml

200

mlH

2O

,bo

iling

chip

s,50

ml2

0%N

aOH

inK

jeld

ahlf

lask

.A

ttach

flask

toth

edi

still

atio

nap

para

tus

with

the

colle

ctio

ntu

befr

omth

eco

nden

ser

imm

erse

din

abe

aker

cont

aini

ng10

0m

lsa

tura

ted

H 3BO

3so

lutio

n.B

oilf

lask

and

dist

illov

er10

0m

l.R

emov

ebe

aker

from

colle

ctio

ntu

bebe

fore

rem

ovin

ghe

atso

urce

.A

ddm

ethy

lora

nge.

0.1

NH

Cl

Yel

low

-red

NH 4

HF 2

(oz/

gal)

5m

l30.

761

3N

Zin

cC

hlo

rid

e

Zn

2m

l10

0m

lH2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eZ

n(o

z/ga

l)5m

l34.

358

3M

Cl

1m

l10

0m

lH2O

,1

mlK

2C

rO4.

0.1

NA

gNO 3

Yel

low

-red

Cl(

oz/g

al)5

ml3

4.72

73

N

Zin

cC

yan

ide

Zn

2m

l10

0m

lH2O

,10

mlp

H10

buffe

r,E

BT

pow

der,

and

15m

l10%

form

alde

hyde

.0.

1M

ED

TA

Red

-blu

eZ

n(o

z/ga

l)5m

l34.

358

3M

555

Tab

leV

III.

Tes

tM

etho

dsfo

rE

lect

ropl

atin

gS

olut

ions

(co

nt.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Tot

alN

aCN

1m

l10

0m

lH2O

,20

ml2

0%N

aOH

,an

d10

ml1

0%K

I.0.

1N

AgN

O3

Cle

ar-t

urbi

dT

otal

NaC

N(o

z/ga

l)5m

l313

.069

3N

NaO

H5

ml

25m

lH2O

,5

mls

ulfo

-ora

nge.

1.0

NH

Cl

Ora

nge-

yello

wN

aOH

(oz/

gal)

5m

l31.

067

3N

Na 2

CO

310

ml

100

mlh

otH 2

O,

35m

l10%

Ba(

NO 3

) 2,

allo

wto

settl

e,fil

ter,

was

hfil

ter

twic

ew

ithho

tH

2O

,tr

ansf

erfil

ter

pape

ran

dpr

ecip

itate

toa

beak

er,

add

100

mlH 2O

,an

dm

ethy

lora

nge.

1.0

NH

Cl

Ora

nge-

pink

Na 2C

O3

(oz/

gal)

5m

l30.

707

3N

ED

TA

,et

hyle

nedi

amin

ete

tra

acet

icac

id;

PA

N,

pero

xyac

etyl

nitr

ate.

a Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

556

Tab

leIX

.T

est

Met

hods

for

Ele

ctro

less

Pla

ting

Sol

utio

ns

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Co

pp

er

Cu

20m

l10

0m

lH2O

,aco

nc.

NH 4

OH

tode

epbl

ue,

heat

to14

0˚F

,an

dad

dpe

roxy

acet

alni

trat

e.

0.1

ME

DT

AP

urpl

e-gr

een

Cu

(g/L

)5m

l33.

177

3M

NaO

H5

ml

150

mlH

2O

.T

itrat

eto

pH10

.5,

usin

ga

pHm

eter

prev

ious

lyst

anda

rdiz

edto

pH10

.0.

0.1

NH

Cl

NaO

H(g

/L)5

ml3

8.0

3N

HC

HO

5m

l10

0m

lH2O

.A

djus

tpH

to9.

0,us

ing

apH

met

erpr

evio

usly

stan

dard

ized

topH

10.0

.A

dd25

mls

odiu

msu

lfite

solu

tion,

stir

1m

inut

e.T

itrat

eto

pH9.

0(t

hese

ml

are

used

for

the

calc

ulat

ion)

.

0.1

NH

Cl

HC

HO

(g/l)

5m

l316

.232

3N

Nic

kel

Ni

5m

l10

0m

lH2O

,20

mlc

onc.

NH 4

OH

,an

dm

urex

ide

pow

der.

0.1

ME

DT

AO

rang

e-pu

rple

Ni(

oz/g

al)5

ml3

1.56

63

M

NaH

2P

O2·H

2O

5m

lU

segl

ass-

stop

pere

dio

dine

flask

.A

dd5

mlc

onc.

H 2S

O4

and

50m

l0.1

Nio

dine

solu

tion.

Sw

irlto

mix

,st

oppe

rfla

sk,

and

plac

ein

dark

for

30m

inut

es,

then

add

star

chso

lutio

n.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssN

aH2P

O2·H

2O

(oz/

gal)

5(m

lI2

3N

-I2

2m

lN

a 2S 2

O3

3N

-Na 2

S 2O

3)

31.

413

Tin

Sn2

12

ml

100

mlH

2O

,25

ml5

0%H

Cl,

10m

lst

arch

solu

tion,

add

bica

rbon

ate

durin

gtit

ratio

n.

0.1

NK

I-K

IO3

Cle

ar-b

lue

Sn

(oz/

gal)5

ml3

3.95

63

N

ED

TA

,et

hyle

nedi

amin

ete

tra

acet

icac

id.

a Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

557

Tab

leX

.T

est

Met

hods

for

Ano

dizi

ngS

olut

ions

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Ch

rom

icC

rO3a

10m

lof

stoc

k10

mls

ampl

ein

to50

0m

lvol

umet

ric.

Pip

ette

10m

lof

stoc

k,ad

d10

0m

lH

2O

,b2

gam

mon

ium

biflu

orid

e,15

ml

conc

.H

Cl,

15m

l10%

KI,

and

star

chso

lutio

n.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

rO 3(o

z/ga

l)5

ml3

22.2

193

N

Fre

eC

rO3

25m

l10

0m

lH2O

.T

itrat

eto

pH3.

05,

usin

ga

pHm

eter

prev

ious

lyst

anda

rdiz

edto

pH4.

0.

1.0

NN

aOH

Col

orle

ss–p

ink

Fre

eC

rO 3(o

z/ga

l)5

ml3

0.53

33

N

Su

lfuric

Tot

alH

2S

O4

5m

l10

0m

lH2O

and

phen

olph

thal

ein.

1.0

NN

aOH

Col

orle

ss-p

ink

Tot

alH

2S

O4

(oz/

gal)

5m

l31.

308

3N

Fre

eH 2

SO

45

ml

100

mlH

2O

,10

mlK

Fso

lutio

n,an

dph

enol

phth

alei

n.1.

0N

NaO

HC

olor

less

-pin

kF

ree

H 2SO

4(o

z/ga

l)5

ml3

1.30

83

N

Al

Al(

oz/g

al)5

(mlN

aOH

for

Tot

alH

2S

O4

2m

lNaO

Hfo

rfr

eeH 2

SO

4)

30.

240

3N

a See

also

alte

rnat

em

etho

din

Fig

.2.

b Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

558

Tab

leX

I.T

est

Met

hods

for

Aci

dD

ips

and

Ele

ctro

polis

hing

Sol

utio

ns

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

HC

2H

3O

210

ml

100

mlH

2O

aan

dph

enol

phth

alei

n.1.

0N

NaO

HC

olor

less

-pin

k%

wt

HC

2H

3O

2(1

00%

)5(m

l30.

6005

3N

)/s.

g.so

lutio

nH

3C

6H

5O

7·H

2O

(Citr

icac

id)

10m

l10

0m

lH2O

and

phen

olph

thal

ein.

1.0

NN

aOH

Col

orle

ss-p

ink

%w

tH

3C

6H

5O

7·H

2O

5(m

l30.

7005

3N

)/s.

g.so

lutio

nH

BF 4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

BF

4(1

00%

)5(m

l30.

8781

3N

)/s.

g.so

lutio

nH

Cl

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

Cl(

100%

)5

(ml3

0.36

463

N)/

s.g.

solu

tion

HF

2g

100

mlH

2O

and

phen

olph

thal

ein.

(Not

e:us

epl

astic

labw

are.

)1.

0N

NaO

HC

olor

less

-pin

k%

wt

HF

(100

%)5

(ml3

2.00

13

N)/

wt

HN

O3

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

NO

3(1

00%

)5(m

l30.

6301

3N

)/s.

g.so

lutio

nH

3P

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

3P

O4

(100

%)5

(ml3

0.98

003

N)/

s.g.

solu

tion

H2S

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

2S

O4

(100

%)5

(ml3

0.49

043

N)/

s.g.

solu

tion

HN

O3

1H

F10

ml

100

mlH

2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

Am

l1

ml

100

mlH

2O

,A

lizar

in,

1.0

NN

aOH

topi

nk,

2%H

NO 3

drop

wis

efr

ompi

nkto

yello

w,

3m

lflu

orid

ebu

ffer.

0.1

NT

h(N

O 3) 4

Yel

low

-pin

kB

ml

%w

tH

NO

3(1

00%

)5[(

Am

l3

N2

103

Bm

l3N

)3

0.63

01]/s

.g.

solu

tion

%w

tH

F(1

00%

)5(B

ml3

20.0

063

N)/

s.g.

solu

tion

H3P

O4

1H

2S

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

Am

lA

ddph

enol

phth

alei

nto

the

solu

tion

abov

e.1.

0N

NaO

HP

urpl

e-re

dB

ml

%w

tH

2S

O4

(100

%)5

[(A

ml

2B

ml)

30.

4904

3N

]/s.g

.so

lutio

n%

wt

H3P

O4

(100

%)5

(Bm

l30.

9800

3N

)/s.

g.so

lutio

nH

2S

O4

1H

2O

2H

2S

O4

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

NaO

HR

ed-y

ello

w/g

reen

%w

tH

2S

O4

(100

%)5

(ml3

0.49

043

N)/

s.g.

solu

tion

559

Tab

leX

I.T

est

Met

hods

for

Aci

dD

ips

and

Ele

ctro

polis

hing

Sol

utio

ns(c

on

t.)

Ba

thS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

H2O

22

ml

100

mlH

2O

and

25m

l20%

H 2SO

4.

0.1

NK

MnO

4C

olor

less

-pin

k%

wt

H 2O

2(1

00%

)5(m

l328

.345

3N

)/s.

g.so

lutio

nC

rO3

1H

2S

O4

CrO

3

10m

lof

stoc

k10

-mls

ampl

ein

to50

0m

lvol

umet

ricfla

sk.

Pip

ette

10m

lof

stoc

k,ad

d10

0m

lH

2O

,2

gam

mon

ium

biflu

orid

e,15

ml

conc

.H

Cl,

10m

l10%

KI,

and

star

chso

lutio

n.

0.1

NN

a 2S 2

O3

Blu

e-co

lorle

ssC

rO 3(o

z/ga

l)5

ml3

22.2

193

N

H2S

O4

25m

l10

0m

lH2O

,10

0m

lred

ucin

gso

lutio

n,bo

il30

min

utes

,re

mov

efr

omhe

at,

add

50m

l10%

Ba(

NO 3

) 2,

100

mlh

otH 2

O.

Allo

wso

lutio

nto

stan

dfo

r3–

4ho

urs,

heat

solu

tion

tobo

iling

.F

ilter

inta

red

Goo

chcr

ucib

le,

was

hpr

ecip

itate

with

hot

H2O

,dr

yin

oven

at11

0˚C

,co

olin

desi

ccat

or,

and

wei

gh.

100%

H 2S

O4

(oz/

gal)

5(w

eigh

tin

gram

sof

prec

ipita

te)3

2.24

1

a Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

560

Tab

leX

II.T

est

Met

hods

for

Alk

alin

eC

lean

ers

So

lutio

nS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

Na 2

O25

ml

100

mlH

2O

aan

dm

ethy

lora

nge.

1.0

NH

Cl

Yel

low

-ora

nge/

red

Na

2O

(oz/

gal)

5m

l30.

165

3N

Na 2

CO

31

NaO

H10

ml

100

mlH

2O

and

sulfo

oran

ge.

1.0

NH

Cl

Ora

nge-

yello

wB

ml

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

Na 2

CO

3(o

z/ga

l)5

(Am

l2

Bm

l)30.

707

3N

NaO

H(o

z/ga

l)5B

ml3

0.53

33

NN

aOH

1N

aCN

NaO

H10

ml

100

mlH

2O

and

sulfo

oran

ge.

1.0

NH

Cl

Ora

nge-

yello

wN

aOH

(oz/

gal)

5m

l30.

533

3N

NaC

N10

ml

100

mlH

2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dN

aCN

(oz/

gal)5

ml3

1.30

73

NN

a 2C

O3

1N

aCN

10m

l10

0m

lH2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

10m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dB

ml

NaC

N(o

z/ga

l)5B

ml3

1.30

73

NN

a 2C

O3

(oz/

gal)

5(A

ml

3N

2B

ml

3N

)3

0.70

7N

a 2C

O3

1N

a 3P

O4

10m

l15

0m

lH2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

Boi

labo

veso

lutio

n5

min

utes

,co

ol,

and

add

phen

olph

thal

ein.

1.0

NN

aOH

Col

orle

ss-p

ink

Bm

l

Na 3

PO

4(o

z/ga

l)5

Bm

l32.

1863

NN

a 2C

O3

(oz/

gal)

5(A

ml

3N

22

3B

ml3

N)

30.

707

Na 3

PO

41

NaC

N1

Na 2

SiO

3·5

H2O

10m

l15

0m

lH2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

Boi

labo

veso

lutio

n5

min

utes

,co

ol,

and

add

phen

olph

thal

ein.

1.0

NN

aOH

Col

orle

ss-p

ink

Bm

l

10m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dC

ml

Na 3

PO

4(o

z/ga

l)5

Bm

l32.

1863

NN

aCN

(oz/

gal)5

Cm

l31.

307

3N

Na 2

SiO

3·5

H2O

(oz/

gal)

5(A

ml

3N

22

3B

ml3

N2

Cm

l3N

)3

1.41

4

561

Tab

leX

II.T

est

Met

hods

for

Alk

alin

eC

lean

ers

(co

nt.)

So

lutio

nS

am

ple

Siz

eR

ea

ge

nts

(To

be

ad

de

din

ord

er

liste

d)

Titr

an

tC

olo

rC

ha

ng

eC

alc

ula

tion

s(m

l,N

,M

-titr

an

t)

NaO

H1

Na 2

CO

31

Na 3

PO

4

10m

l15

0m

lH2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

Boi

labo

veso

lutio

n5

min

utes

,co

ol,

and

add

phen

olph

thal

ein.

1.0

1.0

NaO

HC

olor

less

-pin

kB

ml

10m

l10

0m

lH2O

and

phen

olph

thal

ein.

1.0

NH

Cl

Pin

k-co

lorle

ssC

ml

NaO

H(o

z/ga

l)5(2

3C

ml2

Am

l)3

0.53

33

NN

a 2C

O3

(oz/

gal)

5(A

ml

3N

2B

ml

3N

2C

ml3

N)

31.

414

Na 3

PO

4(o

z/ga

l)5

Bm

l32.

186

3N

NaO

H1

Na 3

PO

41

NaC

N10

ml

150

mlH

2O

and

met

hylo

rang

e.1.

0N

HC

lY

ello

w-o

rang

e/re

dA

ml

Boi

labo

veso

lutio

n5

min

utes

,co

ol,

and

add

phen

olph

thal

ein.

1.0

1.0

NaO

HC

olor

less

-pin

kB

ml

10m

l10

0m

lH2O

and

10m

l10%

KI.

0.1

NA

gNO 3

Cle

ar-t

urbi

dC

ml

Na 3

PO

4(o

z/ga

l)5

Bm

l32.

186

3N

NaC

N(o

z/ga

l)5C

ml3

1.30

73

NN

aOH

(oz/

gal)5

Am

l3

N2

23

Bm

l3N

2C

ml3

N)

30.

533

a Use

deio

nize

dor

dist

illed

wat

erfo

ral

lsol

utio

ns.

562

Table XIII. Alternate Method for Chromic Acid

Degrees Baumé Oz/gal-CrO3 Degrees Baumé Oz/gal-CrO3

1.50 2.1 19.00 29.02.00 2.8 19.50 29.82.50 3.4 20.00 30.63.00 4.1 20.50 31.53.50 4.8 21.00 32.44.00 5.5 21.50 33.34.50 6.2 22.00 34.25.00 6.8 22.50 35.15.50 7.5 23.00 36.06.00 8.2 23.50 37.16.50 8.9 24.00 38.27.00 9.7 24.50 39.17.50 10.4 25.00 40.08.00 11.1 25.50 40.98.50 11.9 26.00 41.99.00 12.6 26.50 42.99.50 13.4 27.00 44.0

10.00 14.2 27.50 45.010.50 15.0 28.00 46.011.00 15.8 28.50 47.111.50 16.5 29.00 48.212.00 17.3 29.50 49.212.50 18.2 30.00 50.213.00 19.1 30.50 51.513.50 19.8 31.00 52.714.00 20.4 31.50 54.014.50 21.2 32.00 55.215.00 22.0 32.50 56.315.50 22.9 33.00 57.516.00 23.7 33.50 58.716.50 24.5 34.00 60.017.00 25.4 34.50 61.217.50 26.3 35.00 62.318.00 27.2 35.50 63.518.50 28.1 36.00 64.8

Procedure: 1. Cool the solution to room temperature after testing.2. Determine the density of the solution with a Baumé hydrometer.3. Read the oz/gal of chromic acid (CrO3) corresponding to this density.

563

Table XIV. Alternate Method for Copper Sulfate

Baumé

Copper Sulfate1Sulfuric Acid

(oz/gal) Baumé

Copper Sulfate1Sulfuric Acid

(oz/gal)

1.5 2.8 14.5 24.72.0 3.5 15.0 25.72.5 4.3 15.5 26.83.0 5.1 16.0 27.83.5 5.9 16.5 28.84.0 6.7 17.0 29.84.5 7.4 17.5 30.85.0 8.2 18.0 31.85.5 9.0 18.5 32.86.0 9.8 19.0 33.86.5 10.6 19.5 34.97.0 11.5 20.0 35.97.5 12.3 20.5 37.08.0 13.1 21.0 38.18.5 13.9 21.5 39.29.0 14.8 22.0 40.49.5 15.7 22.5 41.6

10.0 16.6 23.0 42.810.5 17.5 23.5 43.911.0 18.3 24.0 45.011.5 19.2 24.5 46.112.0 20.0 25.0 47.312.5 21.0 25.5 48.513.0 21.9 26.0 49.713.5 22.9 26.5 51.014.0 23.8 27.0 52.3

Copper sulfate can be determined by taking the Baumé reading. This gives the combined copper sulfate plussulfuric acid. Subtraction of the ounces of acid leaves the ounces of copper sulfate.This method of obtaining the concentration of copper sulfate plus sulfuric acid is not accurate if otheringredients such as aluminum sulfate are present or if the solution is contaminated with iron.

564