Qc pharmceutical
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Transcript of Qc pharmceutical
Some definition:
Qualitative analysis : the chemical analysis that detect the presence of substance in a sample
Quantitative analysis : is the chemical analysis that determines the concentration of a substance in a sample
Volumetric analysis (titrimetric analysis) : is the quantitative chemical analysis carried out by determining the volume of a solution of accurately known concentration which is required to react quantitatively with a measured volume of a solution of the substance to be determined
Gravimetric Analysis is a quantitative analysis is based on the measurement of the weight of a substance of precisely known composition that is chemically related to the analyte. Most often the unknown is precipitated from solution by a reagent and, after separation and drying, is weighed
Instrumental analysis is a field of Analytical chemistry which investigates the analyte via devices or machinery techniques. Like atomic absorption
Redox titration (Oxidation-Reduction titration) is a titration in which the reaction between the analyte and titrant is an oxidation/reduction reaction
Redox reaction (oxidation-reduction reaction) is a reaction that involves transfer of electrons from one substance to another
Complexometric titration is a titration in which the reaction between the analyte and titrant is a complexation reaction
Precipitation titration is a titration in which the reaction between the analyte and titrant involves a precipitation
Concentration is a general measurement unit stating the amount of solute present in a known amount of solution
Solution is a homogeneous mixture of two or more substances
Solute is a minor species in a solution
Solvent is the most abundant component in a solution
Standard solution is the solution of accurately known concentration
Molarity (M) is the number of moles of solute per liter of solution
Normality (N) is the number of equivalents of solute per liter of solution
Molality (m) is the number of moles of solute per kilogram of solvent
Strength of solution (S) is the number of grams of solute per one liter of solution
Weight percent (% w/w) is the number of grams of solute per 100 g of solution
Volume percent (% v/v) is the number of milliliters of solute per 100 ml of solution
Weight-to-volume percent (% w/v) is the number of grams of solute per 100 ml of solution
Part per million (ppm) is the number of micrograms of solute per gram of solution; for aqueous solutions the units are often expressed as the number of milligrams of solute per liter of solution
Part per billion (ppb) is the number of nanograms of solute per gram of solution; for aqueous solutions the units are often expressed as the number of micrograms of solute per liter of solution
Mole Is Avogadro's number of particles (atoms. molecules, ions, or anything else
Molecular weight is the sum of the atomic weights of atoms in the molecular formula
Equivalent weight is the atomic weight of an element or radical divided by its valence; the molecular weight of a compound divided by its combining power in a specific reaction
Gram-equivalent weight is the equivalent weight of an element or compound expressed in grams
Dilution the process of preparing a less concentrated solution from a more concentrated solution
Molar solution is the solution that con¬tains one mole of solute in each one liter of it
Normal solution is the solution that con¬tains one gram equivalent of solute in each one liter of it
Molal solution is the solution that con¬tains one mole of solute dissolved in each one kilogram of solvent
Titration is a procedure in which a solution of accurately known concentration (titrant) is added gradually added to another solution of unknown concentration (analyte) until the chemical reaction between the two solutions is complete
Analyte is a constituent of the sample which is to be studied by quantitative measurements or identified qualitatively
Titrant is the substance that quantitatively reacts with the analyte in a titration. The titrant is usually a standard solution added carefully to the analyte until the reaction is complete. The amount of analyte is calculated from the volume of titrant required for complete reaction
Back titration is a titration in which we add a known excess of one standard reagent to the analyte. Then we titrate the excess reagent with a second standard reagent. A back titration is useful when its end point is clearer than the end point of the direct titration or when an excess of the first reagent is required for complete reaction with analyte
Blank titration is a titration in which we carry out the same procedure without analyte
End point is the point at which the indicator changes color. It is the experimental estimate of the equivalence point in a titration
equivalence point: the moment at which; the Rx is completely and stoichiometric between indicator & unknown
example: all moles HCl reacted with same moles of NaOH as Rx. ratio is 1:1
NaOH + HClNaCl+ H2O
Indicator is a colored compound whose change in color indicates the end point of a titration
Titration curve is a graph showing the progress of a titration as a function of the volume of titrant added
Neutralization Titrations (acid–base titration) A titration in which the reaction between the analyte and titrant is an acid–base reaction
Acid
Arrhenius : a compound which releases hydrogen ions (H+) in solution
Bronsted-Lowry : a compound containing detachable hydrogen ions
Lewis : a compound that can accept a pair of electrons from a base
Base
. Arrhenius : a compound that produces hydroxide ions in aqueous solution
Bronsted-Lowry : a molecule or ion that captures hydrogen ions
Lewis : a molecule or ion that donates an electron pair to form a chemical bond
Strong acid is an acid that completely dissociates into hydrogen ions and anions in solution
Strong base is a base that completely dissociates into ions in solution
Acid-base indicator (Neutralization indicator) is a weak acid or a weak base. The undissociated form of the indicator has a color different from the color of its ionized part. These substances change their color according to variation of pH of medium
External indicator : it's detection of the end point outside conical flask
pH is the negative logarithm of the H+ concentration
Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion
Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion
Oxidizing agent is a substance which oxidize other substance and it self is reduced. - e.g. KMnO4, K2Cr2O7 and I2
Reducing agent is a substance which reduce other substance and it self is oxidized. - e.g. C2O2H4, FeSO4 and Na2S2O3
Redox indicators are highly colored dyes that are weak reducing or oxidizing agents that can be ox¬idized or reduced; the colors of the oxidized and reduced forms are different
Self indicator is the indicator in which the titrant or analyte itself act as indicator (i.e. change their color at end point
Iodimetry direct titrations with I2
Iodometry titration of iodine produced from chemical reaction
Buffer solution : a solution which resistance change in pH
Solubility Product : it's the product of the ion concentration of a sparingly soluble electrolyte
Post Precipitation : secondary precipitation of a foreign substance on the particles of the primary precipitation
Co-Precipitation : Contamination of the precipitate with substance which are normally soluble under the precipitation condition , due to adsorption or occlusion
Masking Process : masking agent is reagent that protect some components
Adsorption : a phenomena which forms when a gas or vapor is brought in contact with an evacuated solid
Double Salt : two simple salt have a properties in aquas state and have another properties in solid state
Formula weight : No. of atoms which exist in the compound
Molecular Weight : it's sum of all atomic weights of atoms of compound
Hydrolysis : reaction of substance with water or it's ions
Mole fraction : the number of moles of a component of a mixture divided by the total number of moles in mixture
Co-ordination bond : transfer of lone pair of electrons from non metal atom ( ligand ) to metal atom
Co-ordination number : the number of Co-ordination bond around the central metal in Co-ordination sphere
Ligand : anion or natural molecule which contain unpaired electrons
Order of reaction : it's sum of all power of the conc. of the reactant
rate of reaction : decrease of concentration per unit time of one of the reactant
Kc : an equilibrium const. in terms of molar concentration
Kp : an equilibrium const. in terms of partial pressure
Ka( acid ionization const. ) : is equilibrium const. of chemical reaction involving weak acid in aqueous solution
Ksp( solubility product const. ) : is the equilibrium const. for a solid substance dissolving in aqueous solution
viscosity : resistance of flow of liquid due to power between the layer of liquid
Titration& Types of Titration
Titration is a procedure in which a solution of accurately known concentration (titrant) is added gradually added to another solution of unknown concentration (analyte) until the chemical reaction between the two solutions is complete
Analyte is a constituent of the sample which is to be studied by quantitative measurements or identified qualitatively
Titrant is the substance that quantitatively reacts with the analyte in a titration. The titrant is usually a standard solution added carefully to the analyte until the reaction is complete. The amount of analyte is calculated from the volume of titrant required for complete reaction
Types of titration
1. Acid –base titration :
2. Oxidation –reduction(Redox) titration :
3. Precipition titration :
4. Complexometrictitration :.
1. Acid –base titration :
Acid-base indicator (Neutralization indicator) is a weak acid or a weak base. The undissociated form of the indicator has a color different from the color of its ionized part. These substances change their color according to variation of pH of medium
Neutralization Titrations (acid–base titration) A titration in which the reaction between the analyte and titrant is an acid–base reaction
When we titrate the sample by standard soln. of base in burrete is called (acidity test )
When we titrate the sample by standard soln. of acid in burrete is called (alkalinity test )
End point is the point at which the indicator changes color. It is the experimental estimate of the equivalence point in a titration
Indicator is a colored compound whose change in color indicates the end point of a titration
ph.ph. is indicator in titration of strong alkalies against strong or weak acids
Methyleorange . is indicator in titration of strong acids against strong or weak alkalies
No indicator gives correct result in the titration of weak acids against weak acids against bases
Strong acid is an acid that completely dissociates into hydrogen ions and anions in solution
Strong base is a base that completely dissociates into ions in solution
1. . Oxidation –reduction(Redox) titration :
Based on oxidation reduction reaction
The chemical Rx,in which occur transfer of electron(loss or gain of electrons)among the reacting ions in aqeous soln.
Some these titrations are named after the reagent used as (permanganate KMnO4,dichromate K2Cr2O7,iodimetric by I2 ,iodometric by Na2S2O3)
Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion
Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion
Oxidizing agent is a substance which oxidize other substance and it self is reduced. - e.g. KMnO4, K2Cr2O7 and I2
Reducing agent is a substance which reduce other substance and it self is oxidized. - e.g. C2O2H4, FeSO4 and(sodium thiosulphate ) Na2S2O3
Redox indicators are highly colored dyes that are weak reducing or oxidizing agents that can be oxidized or reduced; the colors of the oxidized and reduced forms are different
Q:What the difference between iodimetric&iodometric?????
Iodimetry direct titrations with I2
Iodometry titration of iodine produced from chemical reaction
1. Precipition titration :
Based on formation of insoluble ppt,when soln. of 2 reacting substances are contact with each other .
AgNo3+NaCl =AgCl+NaNo3
When AgNo3 is reacted with NaCl; thus White ppt. of AgCl is formed
Such titrations involves AgNo3 are called (Argentometric)
1. Complexometric titration
Undissociated complex is formed at the equivalence point
These titrations are superior to precipitation titrations as there is No error due to co-precipitations (Co-Precipitation : Contamination of the precipitate with substance which are normally soluble under the precipitation condition , due to adsorption or occlusion)
EDTA(ethylene diamine tetra acetic acid ) is useful reagent that forms complexes with metals
In the form of disodium salt; its used to estimate Ca ions& Mg ions in presence of (Eriochrome black-T)(EBT)indicator.
EDTA is considered as a Ligand : anion or natural molecule which contain unpaired electrons
Co-ordination bond : transfer of lone pair of electrons from non metal atom ( ligand ) to metal atom
Co-ordination number : the number of Co-ordination bond around the central metal in Co-ordination sphere
NOTES:
Q: WHAT the difference between end point & equivalence point ??
End point is the point at which the indicator changes color. It is the experimental estimate of the equivalence point in a titration
equivalence point: the moment at which; the Rx is completely and stoichiometric between indicator & unknown
example: all moles HCl reacted with same moles of NaOH as Rx. ratio is 1:1
NaOH + HCl = NaCl+ H2O
Back titration is a titration in which we add a known excess of one standard reagent to the analyte. Then we titrate the excess reagent with a second standard reagent. A back titration is useful when its end point is clearer than the end point of the direct titration or when an excess of the first reagent is required for complete reaction with analyte
Blank titration is a titration in which we carry out the same procedure without analyte
Titration curve is a graph showing the progress of a titration as a function of the volume of titrant added
Indicator is a colored compound whose change in color indicates the end point of a titration
Disadvantages of indicators :
1-visual error
2-each indicator has specific PH range
3-in turbid soln.&colouredsoln.;the change in colour in colour isn’t obvious.
*Acid
Arrhenius : a compound which releases hydrogen ions (H+) in solution
Bronsted-Lowry : a compound containing detachable hydrogen ions
Lewis : a compound that can accept a pair of electrons from a base
*Base
Arrhenius : a compound that produces hydroxide ions in aqueous solution
Bronsted-Lowry : a molecule or ion that captures hydrogen ions
Lewis : a molecule or ion that donates an electron pair to form a chemical bond
The electric cell :
In presence of resistance wire ; electron pass from cathode to anode & electric current from anode to cathode .
In absence of resistance wire ; we replace it by liquid soln. that is called electrolyte that have 2 types : Strong electrolyte: the soln. have completely ionized .e.g: HCL that dissociated into H+& CL-
ions Weak electrolyte: the soln. have partially ionized . e.g: NH4OH that dissociated into NH4
+& OH- ions
The resistance in resisrance wire depend on length & area surface. The resistance in electrolyte soln. depend on ions movement that opposite to each other as +ve
ions go to –ve electrode and the –ve ions go to +ve electrode .thus +ve ions will face –ve ions thus occur resistance to each other .
In presence of electrolyte; ions carry electrons from +ve electrode to –ve electrode ;Firstly,CL-ions around +ve electrode (Anode)to give electrons into this electrode by(Redox)to go to the cathode electrode and CL- ions turns into CL- ions turns into CL2 gas in the soln. by loss of electrons that is carried on ions , then H+ ions around the –ve electrode cathode to gain electrons from the cathode by redox and turn into H2 gas
PHmeter:
Use for measuring the PH that is either the conc. or activity of H+ ions in aqueous soln. PH indicate if the soln. is acidic or basic ; but isn’t a measure of acidity or alkalinity. PH meter consists of glass electrode connected to electronic meter that measure the PH
reading.
NOTE: Glass electrode: is electrode contain reference electrode &working electrode in the
same set. PH of water is (5-7) at 250C PH=-log{H+}
Q: Why water is acidic ??
Because water have Ca+2,Mg+2 ions that make water hardness ; where the Ca+2 ions attract the Oxygen from H2 to make strong &nearthus occur small bond between (Ca&O)but make the bond of O with each H atom is long &weak , thus each H ions will be free in the medium thus the water become acidic .
Conductivitymeter:
To determine conc. of substance by measuring its conductance. R=(P*L)/A its unit is (Ohm) ; P=specific resistance(resistance of 1 cm3 of electrolyte ); L=length
of wire ; A= area surface ; R=resistance G=1/R its unit is (Semens)or(S)or (Ohm-1) ; G = conductivity (its ability of electrolyte to
conduct electric current) Conductivity of water at 250C is 1.3 Factors on conducitivity:
1) Number of ions.2) Mobility of ions.
Types of conductivity :a) Specific conductivity: conductance of 1 cm3 of soln.b) Molar conductivity: conductance of 1 mole of soln.c) Equivalent conductivity:conductance of 1 gm equivalent of soln.
Potentiometer:
To determine conc. of substance by measuring electrode potential of soln. in condition (No current flow)
End point is reached when suddenly change in potential of working electrode. Combined electrode : e.g: glass electrode. is electrode contain reference electrode &working
electrode in the same set. Reference electrode ; has const. potential or zero ; don’t depend on conc. of analyte. Like SHE,
Calomic electrode , Ag/AgCL Working electrode : its potential depend on conc. of analyte or metal ion.
Ecell=Eworking-Ereference Nernest equation : Ecell= E0+((R*T)/(n*F))*ln a E0= standard electrode potential ; n=number of electrons; R=gas const.,T= temp., F=Faraday
const.,a=activity(a=conc.*activity coefficient)
Gravimetric analysis Its quantitive technique involves the conversion of element to be determined from soluble form to insoluble form and isolated it by filteration ,then weighting it .
1. Precipitation2. Digestion3. Filteration&washing4. Drying,ignition&weighting5. Calculation
1-precipition:
Properties of good precipitate
1. Have good physical form2. Have definite chemical composition3. Must be pure or extrapure
Contamination of precipitation
a) Co-precipition:its contamination of ppt by another element present in the mother liquid b) Past-precipition:its contamination involves precipition of second ppt. on surface of first ppt.
Q:How reduce contamination?
1) Recrystallization(smal crystals converts to large crystals)2) Removal of interfering ions 3) Fast isolation or filteration for the formed ppt.
2-Digestion:leaving the ppt in contact with the mother soln. of period of time
3-Filteration:isolation of ppt from the mother soln. by (ashless filter paper – Buchner system )
4-Washing:process aims to removal of surface adsorbed ions
5-Drying:occur at low temp. Iginition:occur at high temp.
Drying&Iginition are used to determine the analyte
Note:
Dessicator(dry box)
-dessicator is covered glass container for storage of objects in dry atmosphere
-it is charger with drying agent as silica gel or anhydrous Caso4&anhydrous CaCL2
LOSS ON Dyring test:
a) Weigt the dryied empty petridish(tare wt)w1b) Then put (1gm)of sample on thisthe dryied empty petridish(w2=1gm)c) Then put this petridish onto oven at 105cd) Out the petridish to cool at the dessicatore) Weight this petridish (w3)then calculate by (w4=w3-w1)
W3=weight of drying sample………..W(H2O)=W4-W2
LOSS ON Drying=( W(H2O)/W2)*100
Sulphated Ash test :
a) Weight the dryied empty crucible (tare wt)(Ec)b) Then put (1gm)of sample on empty crucible (Sw)c) Then add 1ml H2SO4 Conc.d) Put this crucible at flame to heat till No longer white fumese) Then put this crucible onto the muffle at 850C for certain period time(acc.
to pharmaceopia)f) Out the crucible to cool at the dessicatorg) Weight the crucible (Ac);then calculate: Aw=Ac-Ech) Repeat this test 3 times then take average
Aw:ashwt from(Aw=Ac-Ec)………………,Ac:(ash+crucible)wt………….Ec:empty crucible wt………………Sw:sample weight as (1gm)
%Ash=(Aw/Sw)*100
Question:What is the difference between Sulfated ash & Residue on iginition ?
H2SO4 conc. is used in Sulfated ash test ;H2SO4conc.is not used inResidue on iginition
Chromatography theory: solutes to be separated depend on distribution between 2 phases (mobile phase &stationary phase)
For Example in HPLC; sample is complex mix. Of organic compound that is dissolved in organic solvent by HPLC that make separation & determination of this mix. quantitative or qualitatitve
Chromatogram: it’s a graphical representation (plot) of chromatographic separation process in which the conc. is plotted against the time
Injection point: point at chromatogram that indicate that the sample injected in column Retention time :
-time elapsed between injection point &maximium peak of the solute
- is the time that each component takes to come off the column
- can be used to help identify components
Types of resolution:1. Base line resolution: occur complete separation (each component have a peak refers to
indicate it )2. Partial resolution:(each peak of each component is very nearly to each other )3. Zero resolution:(each peak of each component is found in one peak in the chromatogram)
Column of st.phase have large number of separate layers that called theoretical plates(when no. of the theoretical plates increase; there occur perfect efficiency of chromatography )
The Theoretical plates (N): 1. To measure column efficiency 2. To measure of peak sharpness which is important for detection of trace component
peak sharpness is preferred than peak broadening due to occur overlapping of peak broadening thus peak sharpness is apprear fast
types of liquid chromatography: (NPLC,RPLC)1. NPLC: Normal Phase Liquid Chromatography (polar st. phase as silica particles &non
polar m.phase as hexane)
2. RPLC: Reversed Phase Liquid Chromatography(polar m. phase as silica particles &non polar st.phase as hexane)
Displacementer: The substance that found in m.phase ;and have the ability to react with st. phase than
all types of solutes It replace the solute that found in column; whereas one component which has weaker
interaction with column and strong interaction with m. phase while elute firstly,while one component which has strong interaction with column and weak interaction with m.phase will be eluted later
Disadvantage of displacementer ; there is problem in analytical scale ; because No complete elution of each component of mix (presence of mixed zones ) that called Tail region{its conc. contain mix of 2 adjacent solutes components}
Tail region: (if there is peak A & peak B , the peak A may be mixed with peak B; because there are remain amount of peak A But B>A )
Frontal analysis: in which; dilute soln. of mix.(m.phase) is continuously added on one column;solutes get out from that have st. phase based on interaction between solutes &st.phase
Elution types a) Isocreaticeution.(composition of m.phase doesn’t change during one separation
process)i. Stepwise m.phase(in which; different m.phase are used at different times)ii. Only one m.phase(used,not changed in composition during process)
b) Gradient elution (composition of m.phase change during one separation process, can changing from polar to non polar or opposite is right )
Shapes of st.phase: A. Column- chromatography (st.phase is inside a tube;andm.phase moves through the
column by influence of gravity or pressure )i. Packed column (st.phase is solid; it completely packed in column and m.phase is
as inert matter)ii. Open tubular column (st.phase coats inside the wall in the tube leaving empty
path for m.phase)B. Planar- chromatography (st.phase is inside a plat TLC or paper;andm.phase moves
through the plate or paper by influence of capillary action through the plate or paper by influence of capillary action; Examples: paper chromatography ;TLC thin layer chromatography plate )
Separation mechanism types :1. Affinity chromatography
Separation depend on interaction between solute &st.phase2. Ion-exchange chromatography
Separation depend on difference in the charge of solute St.phase is resigns or polymer with acid or basic group
3. Chiral chromatography
Is used for separation of chiral compounds If solutes&st.phaseare chiral compounds and m.phaseisn’t chiral compound If solutes&st.phasearen’t chiral compounds and m.phaseis chiral compound St.phase is cellulose ,amaylase derivatives, protiens , peptids , cyclodextrin
4. Size exclusion chromatography:Ex: (LSC)Liquid Solid Chromatography Separation depends on difference in size of the solute(small size get out down;but large
size remains) Examples;(gel filteration):aqueous liquid m.phase -gel permation):organic liquid
m.phase St.phase is polymer or porous silica
5. Adsorption chromatography:Ex: (LSC)Liquid Solid Chromatography Separation depends on difference in adsorption affinities of mix. components to
st.phase St.phase is silica
6. Partition chromatography:Ex: (LLC)Liquid Liquid Chromatography Separation depends on difference in distribution of mix. components between 2 liquid
phases (liquid m.phase&liquid st. phase )
Paper chromatography ;TLC thin layer chromatography plate Paper chromatography: is technique of separation &identification of compounds by
moving solvent(on sheets or strips of filter paper) TLC thin layer chromatography plate: is technique of separation &identification of
compounds by moving solvent(on thin layer plate as silica gel coated on plastic plate) Advantages of TLC over Paper chromatography; TLC is better than paper in resolution
(as give sharpest peak than in paper)in quantification &in TLC use corrosive agent Types of paperchromatography:
i. Ascending chromatography:(in which,solvent travels from down to up through filter paper or TLC by capillary action )
ii. Descending chromatography:(in which,solvent travels from up to down through filter paper or TLC by capillary action ; tere are volatile substances,to overcome it by gravity; Descending is fast than Ascending)
iii. One dimension chromatography: (only one solvent is applied)iv. Two dimension chromatography: (in which 2 solvents at right angle are
applied;we make right angle to avoid overlapping) TLC Method:
You put alittle spot of standard &test soln. by micropipette on TLC plate;you put TLC plate into the TLC jar that have m.phase;wait a little bit for m.phase to travel upwards;pull it out of the chamber; then using detection soln. that was prepared and put it on the plate then either (use uv-lamp to see what spots are there)or (use the oven at 105 C at certain period of time to see what spots are
there)and then try to compare than 2spots in terms of polarity and calculate (RF) value
Mechanism of TLC =Paper chromatography: Is result of 2 forces
1) Propelling force: that depend on solvent flow, solubility…when RF value increase
2) Retarding force : that depend on partition, adsorption…….when RF value decrease
RF(Retention Factor)o RF=propelling force +retarding forceo RF is quantitative indication of how far a particular compound travels in
particular solvento RF value is good indicator of unknown compounds &known compoundo When 2 compounds are likely similar or identical; the RF value for
unknown compound is closed or same to known compoundo RF =D1/D2 where ;
D1= distance that color traveled,measuredfrom center of the band of color to another center of the end point D2=total distance that solvent traveled
o If RF=1; indicate polarity solvent(propelling force >retarding force)thus solute is less resistance to move
o If RF=zero; indicate No polar solvent(propelling force <retarding force) thus solute is more resistance to move
o If RF=0.3or 0.7 or any number between (zero to one ) may be also soluble
HPLC(High Pressure Liquid Chromatography)
It is used for 1) For separating mixtures either to analyze the mix. or to separate a required
product from others in a reaction mixture2) To find the relative amounts of different components in a mixture.
In which; how fast each one moves depends on its relative affinity for the m.phase in the st.phase ;or example , if m.phase is more polar than st.phase ;the more polar components of mix. will tend to move more quickely than the less polar ones
Components of HPLC :(mobile phase,pump. Injection port or autosampler,column, detector,display,waste bottles)
There are pumps; they produce a pressure 150 times that of the atmosphere ,hence the name high pressure liquid chromatography
If single sample is to be run, it is injected into the solvent stream, here in the injection port via a hypodermic syringe
If several samples can be run by loading them into autosamplers that will run them in order without any human intervention.
The pumps force the mixed solvents through the column. The solvent emerging from the column & carrying the separated components of the mix. passes into the detector .
By the detector; electromagnetic reaction between st.phase& solutes by moving m.phase acc. to polarity
Parameter for HPLC : temp.,pressure,wave length, flow rate (ml. per min. ) Types of column :
1) Length 150 mm ,diameter 4.6 mm , pore size 5 micro meter 2) Length 250 mm ,diameter 4.6 mm , pore size 5 micro meter3) Length 300 mm ,diameter 4.6 mm , pore size 5 micro meter
Types of st.phase in the column 1) L1: C182) L7:C83) L10:CN
Factors on retention time :1) Length of column :( when length of column increase; the retention time
increase )2) Flow rate: (when flow rate increase ; the retention time decrease )
NOTE: buffer soln. are used to prevent crystllisation of salts
Some troubleshooting are : temp.,flow rate, PH, degassing m.phase, mixing m.phase , column fouling ,sample injection overloading acc. to number of volume
factors of choice for separation &quantitation by column chromatography :1. stationary phase
a. cross section shape &sizeb. lengthc. morphology of stationary phased. material composition
2. mobile phasea. compositionb. flow rate
3. temp.4. detector5. sample size(volume,concentration)
General Factors Increasing Resolution
Increase column length
Decrease column diameter
Decrease flow-rate
Pack column uniformly
Use uniform stationary phase (packing material)
Decrease sample size
Select proper stationary phase
Select proper mobile phase
Use proper pressure
Use gradient elution
Solubility: 1gm in 1ml=very soluble 1gm in 10ml=free soluble 1gm in 30ml= soluble 1gm in 100ml=slightly soluble 1gm in 300ml=spraingly soluble 1gm in 10,000ml=very slightly soluble 1gm in 100,000ml=practically insoluble
Polarimeter:
Principle of polarimeter: It measure the optical rotation angle of polarized light as it passes through an optically
active fluid. The measured rotation can be used to calculated the value of soln. conc.
Light is in all direction & introduce into the polarizer (filter-like) that polarize the light group in one direction only . so give us plane –polarized light enter the sample tube show us …if the molecule has stereochemistry involved or not :
Once the light come through the sample tube in the organic compounds that was up , down in & basically still up ,down in the end.(so No rotation of light , molecule don’t have Dextro or Levo; these molecules are achiral )
Once the light come through the sample tube in the organic compounds that was up ,down in but changing as rotates ;it will be such as like right –hand rotated;(molecules do rotation of light , molecules have Dextro,Levo; these molecules are chiral compound as rotated left hand or right hand rotated )
Polarimeter advantages: It is used for analysis of optically , active fluids like sugars, lactic acid , tartaric. This method gives information on chemical structure , chirality, and conc. of sample by
measuring the analyte through a ray of ploarised light Application of polarimeter:
Sugar industry Food ,drink &agriculture Pharmaceutical industry Chemical industry
Optical rotation=angle rotation /length of sample tube Specific Optical rotation=angle rotation /(length of sample tube*conc.)
Where :conc.=Wt(gm)/(Vml)
UV ا
Ultraviolet-visible spectrometry tell us about electronic transition in atoms & molecules Compounds that absorb in the visible region (400-800 nm) such as some transition metal compounds and
organic dyes are coloured but others that absorb only in the UV-region (200-400 nm) are colourless. Inside UV-Visible spectrometer;
1) There are 2 light sources , (tungsten lamp) like a car head lamp bulb for giving out visible light & (Deuterium lamp) gives out UV-light .
2) The source produces white light that include all wave lengths, all colours; then light go to (wave length selector)that contains diffraction grating that splits the light into its constituent wave lengths.
3) The single wave length pass to (half silvered mirror synchronized)whereas it cuts the light into 2 beams; one beam pass through the sample cell While other pass through the reference cell ;
Q: compare between double beam & single beam ??-double beam : measure blank & test in one time -single beam : measure blank & test separately
4) Both sample & reference beam are directed to another half silvered mirror synchronized then to photomultiplier (that convert light photon into light current )
5) From photomultipler to detector that compares their intensities and sed single proportional to the ratio of their intensities to the computer that controls the instrument. The logarithum of this ratio gives quantity called (absorbance)(that is measure how much light is being absorbed by the sample that particular wavelength )
NOTES:
UV-Visible are run on solution, light doesn’t normally pass through solid samples To run the spectrum we place some of the solvent in a sample cuvette to act as a blank , a reference .
(there are 2 cuvettes type )-glass or plastic cuvettes is required for work in the visible region of the spectrum.-Quartz cuvettes are needed for work in the UV-range region.
Strong peak(fundamental stranger peak):The electrons transfer from r0of ground state to r0 of excited state ....(A)
Weak peak (overtone peak):The electrons transfer from r0 of ground state to r1 of excited state....(B)
Sharp peak: electron transfer from r3 ground state to r3 excited state but when it back occur at one step.
Broad peak: electron transfer from r3 ground state to r3 excited state but when it back occur at more step.
Karl-Fischer
To determine trace amounts of water in sample. Technique based on a reagent that react with the water in a sample & converts the water into non-conductive
chemical. Reagent is composed of (CO2+Pyridine+Iodine)
Water tests:
1. Appearance: Clear,colourless liquid by visually
2. Conductivity: Result:1.3 S at 250C
3. PH: Result:(5-7) at 250C
4. Total organic carbon: Result:less or equal 0.5 mg/ml
5. Acidity/alkalinity: Method: 10 ml boiled then cooled then 0.05 ml of methyl red soln.Result: soln. is not red color Method: 10 ml boiled then cooled then 0.1 ml of bromothymol blue soln.Result: soln. is not blue colour
6. Oxidizable test: Method: 100ml of sample then add 10 ml H2SO4(1M) then add 0.1ml of (0.02M) KMnO4 then boil for 5min.Result: the soln. remaining faintly pink .
7. Nitrate test: Method: I. Prepare 2 tubes (test tube & STD tube )II. Add 4.5 ml purified water STD in the STD tubeIII. Add 5 ml of sample in the test tube IV. Add 0.4 ml KCL 10% at each tube V. Add 0.5 ml Nitrate STD 2ppm at STD tubeVI. Add 5 ml of H2SO4 conc. At each tubeVII. Add 0.1 ml diphenylamine at each tube Result: blue colour at STD tube &colourless at test tube .
8. Ammonium test: Method:I. Prepare 20 ml of sample then add 1ml of potassium tetraiodomercurate in tube (A)II. Prepare 4ml of NH4 (1ppm STD)+16ml of ammonium -free water+1ml of potassium
tetraiodomercurate in tube (B)Result: (A) tube is not more intensely coloured than tube (B)
9. Heavy metal: Method:I. Heat 20ml to evaourate till volume reach to 20 mlII. Prepare 4 tubes (test tube,STD tube, blank tube,another tube)respectively.III. Put 12ml of test soln. in the test tube.IV. Put 2ml of test soln. in the test tube + 10ml of standard lead (10ppm) in STD tubeV. Put 2ml of test soln. in the test tube+ 10 ml of H2O in blank tubeVI. Put 5ml of (heavy metal mix. Reagent)that is to Add 1 mL of a mixture of 15 mL of 1M
sodium hydroxide, 5 mL of water and 20 mL of glycerol (85%) , heat in a water bath for 20 seconds, cool and use immediately.+1ml of thioacetamide reagent in the another tube.
VII. Then add 2 ml of (buffer PH3.5) in the first 3tubesVIII. Add 1ml from tube 4 in each first 3 tubesResult:the STD tube is more than test tube in brown colour.
10. Calcium & magnesium: Method: 10ml sample then add 2ml ammonium chloride buffer soln.(PH10)then add 50mg of EBT indicator then add0.5ml of( 0.01M) EDTAResult: pure blue colour
11. Residue on evapouration: Method:i. Evapourate 100ml on water bath and dryii. Bring a beaker and wt it empty dreied,then put 100 ml of sample an evapourate thus wt
this same beaker after cooled in the dessicator.iii. Residue water soluble = Gross wt - Tare wtiv. Tare wt=wt of empty dried beakerv. Gross wt = wt of this beaker after evapouration of its sample.
Result: Maximum 0.001%12. Chloride:
Method: 10ml of sample then add 1ml (2N) HNO3 then 0.2 ml AgNO3 in test tubeResult: No change at 15min
13. Sulphate: Method: 10ml of sample then add 0.1ml HCL(1N) then add 0.1ml (BaCL2)Result: No change at least 1hour
14. Iron test: Method:
i. Prepare 2 Nessler tubes (test tube ,STD tube)ii. Prepare citric soln.(5gm citric acid in 25 ml of H2O)
iii. Add 10 test soln. in the test tube then add 2ml citric soln.iv. Add 10 standard iron reagent (10ppm) in the test tube then add 2ml citric soln.v. Then add 0.1 ml thioglycolic acid
vi. Then add 5ml NH3 conc.vii. Result: (the STD is more than test in pink colour)
Heavy Metals:
Definition:
In general, metallic type of impurities are detected by standard procedure of inorganic qualitative analysis which involve colour and precipitation reaction.
It detects elements with insoluble sulfides [lead (Pb), mercury (Hg), bismuth (Bi), arsenic (As), antimony (Sb), tin (Sn), cadmium (Cd), silver (Ag), copper (Cu), molybdenum (Mo)], it does not identify which is element is present.
This test is based on principle that traces of lead salts if present are converted to lead sulphide by the addition of Na2S to a slightly alkaline solution buffered by a high concentration of ammonium acetate. The brown colour obtained due to the presence of colloidal PbS in the sample solution is compared with that obtained from a known amount of lead.
Pb2+ + H2S → PbS¯ + 2H+
Method:
i. Prepare 4 tubes (test tube,STD tube, blank tube,another tube)respectively.ii. Put 12ml of test soln. in the test tube.iii. Put 2ml of test soln. in the test tube + 10ml of standard lead (10ppm) in STD tubeiv. Put 2ml of test soln. in the test tube+ 10 ml of H2O in blank tube
v. Put 5ml of (heavy metal mix. Reagent)that is to Add 1 mL of a mixture of 15 mL of 1M sodium hydroxide, 5 mL of water and 20 mL of glycerol (85%) , heat in a water bath for 20 seconds, cool and use immediately.+1ml of thioacetamide reagent in the another tube.
vi. Then add 2 ml of (buffer PH3.5) in the first 3tubesvii. Add 1ml from tube 4 in each first 3 tubes
Result : the STD tube is more than test tube in brown colour.
Chloride limit test :
i. Prepare 2 tubes (test tube ,STD tube)ii. Put 5 ml of test soln. in the test tube iii. Put 5 ml of chloride standard reagent (10ppm) in STD tube iv. Put 1ml of AgNO3 in each tube v. Put 1 ml of HNO3in each tube
Result : the STD tube is more than test tube in white ppt .
Sulphate limit test :
i. Prepare 2 tubes (test tube ,STD tube)ii. Put 5 ml of test soln. in the test tube iii. Put 5 ml of Sulphate standard reagent (10ppm) in STD tube iv. Add 1ml of HCL(1N) in each tube v. Add 1ml of BaCL2 in each tube.
Result : the STD is more than test
Iron test:
viii. Prepare 2 Nessler tubes (test tube ,STD tube)ix. Prepare citric soln.(5gm citric acid in 25 ml of H2O)x. Add 10 test soln. in the test tube then add 2ml citric soln.
xi. Add 10 standard iron reagent (10ppm) in the test tube then add 2ml citric soln.xii. Then add 0.1 ml thioglycolic acid
xiii. Then add 5ml NH3 conc.Result: (the STD is more than test in pink colour)
Residue water soluble :
(Sample+impurities) then add water then make filteration thus(sample)and (water+impurities)that occur evapouration .
Residue water soluble = Gross wt - Tare wt Tare wt=wt of empty dried beaker Gross wt = wt of this beaker after evapouration of its sample.
TOC (Total Organic Carbon)
It mean if there are ions in the water sample or not. Mechanism:
i. Washing step:UV &H3PO4&Sodium persulphate convert the carbon into CO2&H2CO3 where H2CO3 to be H+,CO2
- ions to increase conductivity & the curve indicate that the rate of conductivity is high or low.
ii. Sparging step:Remove inorganic carbon portion firstly ; then mean the organic carbon , this method is called (sparging) that occur purging the sample by Nitrogen gas .
Flame photometer:
Is a device used in inorganic chemical analysis to determine the conc. Of certain metal ions, among them sodium,potassium,calcium,Group 1&Group2 metals are quite sensitive to flame photometry due to their low excitation energies.
وغيره والنورمالتي الموالرتي وتعريفات الكيمائية المحاليل تحضير قوانين
Solutions preparation
Solution Solution A solution is a homogeneous mixture composed of two or more
substances. In such a mixture, a solute is dissolved in another substance,
known as a solvent.
SoluteSoluteThe substance which dissolves in a solution
SolventSolventThe substance which dissolves another to form a solution
SaturationSaturationSaturation is the point at which a solution of a substance can dissolve no
more of that substance and additional amounts of it will appear as a
precipitate.
SupersaturationSupersaturationIt refers to a solution that contains more of the dissolved material than
could be dissolved by the solvent under normal circumstances.
Types of solutions Types of solutions Percentage solution
Molar solution
Normal solution
Percentage solutionPercentage solution
Weight/ Weight solution % (w/w)Weight/ Weight solution % (w/w) This type of solution is rarely if ever prepared in the laboratory since it is
easier to measure volumes of liquids rather than weigh the liquid on an
analytical balance.
This type of percent solution is usually expressed as (w/w), where "w"
denotes weight (usually grams) in both cases.
Example: An example of a correct designation for this type of solution is as follows:
10 g/100 g (w/w), which indicates that there are 10 grams of solute for
every 100 grams total
Weight/volume solution % (w/v)Weight/volume solution % (w/v) Weight-volume percentage, (sometimes referred to as mass-volume
percentage and often abbreviated as % m/v or % w/v) describes the mass
of the solute in g per 100 ml of the resulting solution.
Wt of solute (g) = C (required Conc.) X V of solvent (ml)
100
Example: Preparation of 10% (W/V) NaCl solution Preparation of 10% (W/V) NaCl solution
CalculationsCalculations:
so10% (W/V) NaCl solution has 10 grams of sodium chloride dissolved in
100 ml of solution.
Procedure:Procedure:
Weigh 10g of sodium chloride.
Pour it into a graduated cylinder containing about 80ml of water.
Once the sodium chloride has dissolved completely add water to bring
the volume up to the final 100 ml.
Note:
Do not simply measure 100ml of water and add 10g of sodium chloride.
This will introduce error because adding the solid will change the final
volume of the solution and throw off the final percentage.
g/L unite
A gram per liter (g/L) is a unit of measurement of concentration which shows
how many grams of a certain substance are present in one litre of liquid.
Volume /volume solution % (v/v)Volume /volume solution % (v/v)
g/L unite
A gram per liter (g/L) is a unit of measurement of concentration which shows
how many grams of a certain substance are present in one litre of liquid.
V1 of solute (ml) = C2 (required Conc.) X V2 of solvent (ml)
C1 (original solute Conc.)
Volume-volume percentage (abbreviated as % v/v) describes the volume of
the solute in ml per 100 ml of the resulting solution.
Example: Preparation of 30% (V/V) sulfuric acidPreparation of 30% (V/V) sulfuric acid
Calculations: Calculations:
So 30% (V/V) sulfuric acid has 30 ml of sulfuric acid dissolved in 70 ml of
water.
Procedure:Procedure:
Calculate the required volume of solute
Subtract the volume of solute from the total solution volume
Dissolve 30 ml sulfuric acid in a 70 ml of water to bring final volume of
solution up to 100ml.
Note:
When you mix concentrated sulfuric acid and water, you must add acid (AA) to water in ice bath.
Why?
Sulfuric acid reacts very vigorously with water, in a highly
exothermic reaction. Water is less dense than sulfuric acid, so if you pour water on the acid, the reaction occurs on top of the liquid. If you add the acid to the water, it sinks and any wild reactions have to get through the water.
Molar solutionMolar solutionMolecular weightMolecular weightIt is the sum of the atomic weights of all the atoms in a molecule. Also
called formula weight
Mole Mole A mole is also called gram-molecular weight and defined as number of
particles whose total mass in grams was numerically equivalent to the
molecular weight or it is the amount of substance containing the Avogadro
number (6.022 × 1023)
MolarityMolarityMolarity or molar concentration denotes the number of moles of a given
substance per liter of solution.
Molar solution Molar solution It is a solution that contains 1 mole of solute in each liter of solution.
Units of molarityUnits of molarity
Wt of solute (g) = M (mole/l) X M.wt (g/mole) X V (L)
The units for molar concentration are mol/L. These units are often denoted
by a capital letter M (pronounced "molar").
1 mol/l = 1000 mmol/l = 1000000 mol/l = 1000000000 nmol/l
1 mmol/ml = 1 mol/l
1 mol/ml = 1 mmol/l
Name Abbreviation Concentration
Millimolar mM 10-3 molar
Micromolar M 10-6 molar
Nanomolar nM 10-9 molar
Picomolar pM 10-12 molar
Femtomolar fM 10-15 molar
Molarity of solid soluteMolarity of solid solute
Example: Preparation of 1M NaCl solution in 1000 mlPreparation of 1M NaCl solution in 1000 ml
Calculations: Calculations:
Molarity (M) = % X density X 10
M.wt
V1 of solute(ml) = M2 (required molarity) X V2 (required volume) (ml)
M1 (original molarity)
M: the required molarity M.wt: molecular weight of the solute V: total volume in liters
Procedure:Procedure:
Dissolve 58.5 g of NaCl in a 1000 ml (1 liter) of water to prepare 1M NaCl
solution.
Molarity of liquid soluteMolarity of liquid solute To prepare 1M solutions make the following steps:
Calculate the molecular weight of the solute
Calculate the molarity of the solute using the following formula:
Calculate the volume of the solute needed to prepare 1M solution using
the following formula:
Subtract the volume of solute from the total solution volume
Mix both volumes of solute and solvent to reach the total required
volume
Example1:
Preparation of 1M HCL solution in 1000 mlPreparation of 1M HCL solution in 1000 ml % percent Density M.wt
32 1.18 36.5
HCL molarity = 10.345
Volume required from HCL = 96.66 ml
Complete to 1 liter with 903.33 ml distilled water
Example2:
Preparation of 1M HPreparation of 1M H 22SOSO44 solution in 1000 ml solution in 1000 ml% percent Density M.wt
98 1.83 98
H2SO4 molarity = 18.3
Volume required from H2SO4 = 54.64 ml
Complete to 1 liter with 945.36 ml distilled water
Example3:
Preparation of 1M HPreparation of 1M H 22OO22 solution in 1000 ml solution in 1000 ml% percent Density M.wt
30 1.44 34.01
H2O2 molarity = 12.70
Volume required from H2O2 = 78.74 ml
Complete to 1 liter with 921.25 ml distilled water
Normal solutionNormal solutionEquivalent weightEquivalent weightAn equivalent weight is equal to the molecular weight divided by the
valence (replaceable H ions).
NormalNormalA normal is one gram equivalent of a solute per liter of solution.
NormalityNormalityNormality is the total no of gram equivalents of the solute present per liter of the
solution
Normal solutions Normal solutions The definition of a normal solution is a solution that contains 1 gram
equivalent weight (gEW) per liter solution.
Units of NormalityUnits of NormalityThe units for normal concentration are Eq/L. These units are often denoted
by a capital letter N (pronounced "normal").
Eq.wt = M.wt of acid or base
No of H+ in acids or OH- in bases
mEq/L = 0.001 Eq/L
How to calculate equivalent weightHow to calculate equivalent weight
Eq.wt for acids and bases Eq.wt for acids and bases
Examples:
HCL the MW= 36.5 the EW = 36.5
H2SO4 the MW = 98 the EW = 49
H3PO4 the MW = 98 the EW = 32.7
NaOH the MW = 40 the EW = 40
Ca (OH)2 the MW = 74 the EW = 37
Eq.wt = M.wt of salt
No of cations X valency or No of anions X valency
Eq.wt for salts Eq.wt for salts
Examples:
KCL the MW= 74.55 the EW = (74.55 / 1 X 1) = 74.55
CaCl2 the MW= 110.98 the EW = (110.98 / 1 X 2) or (110.98 / 2 X 1) =
55.49
Na2CO3 the MW= 105.98 the EW = (105.98 / 1 X 2) or (105.98 / 2 X 1) =
52.99
Normality of solid soluteNormality of solid solute
Examples: Preparation of 1N NaOH solutionPreparation of 1N NaOH solution Preparation of 1N Ca(OH)Preparation of 1N Ca(OH) 22 solution solution
Wt of solute (g) = N (Eq/l) X Eq.wt X V (L)
Normality (N) = % X density X 10
Eq.wt
Preparation of 1N KCL solutionPreparation of 1N KCL solution
Calculations: Calculations:
N: the required normality Eq.wt: equivalent weight of the solute V: total volume in liters
Procedure:Procedure:
Dissolve 40 g of NaOH in a 1000 ml (1 liter) of water to prepare 1N
NaOH solution.
Dissolve 37 g of Ca (OH)2 in a 1000 ml (1 liter) of water to prepare 1N
Ca (OH)2 solution.
Dissolve 74.55 g of KCl in a 1000 ml (1 liter) of water to prepare 1N KCl
solution.
Normality of liquid soluteNormality of liquid solute To prepare 1N solutions make the following steps:
Calculate the equivalent weight of the solute
Calculate the normality of the solute using the following formula:
V1 of solute(ml) = N2 (required normality) X V2 (required volume) (ml)
N1 (original normality)
Calculate the volume of the solute needed to prepare 1N solution using
the following formula:
Subtract the volume of solute from the total solution volume
Mix both volumes of solute and solvent to reach the total required
volume
Example1:
Preparation of 1N HCL solutionPreparation of 1N HCL solution % percent Density M.wt
32 1.18 36.5
HCL normality = 10.345
Volume required from HCL = 96.66 ml
Complete to 1 liter with 903.33 ml distilled water
Example2:
Preparation of 1N HPreparation of 1N H 22SOSO44 solution solution
% percent Density M.wt
98 1.83 98
H2SO4 normality = 36.6
Volume required from H2SO4 = 27.32 ml
Complete to 1 liter with 972.67 ml distilled water
Dilution of solutionsDilution of solutions Simple DilutionSimple Dilution
A simple dilution is one in which a unit volume of a liquid material of interest
is combined with an appropriate volume of a solvent liquid to achieve the
desired concentration.
The dilution factor is the total number of unit volumes in which your material
will be dissolved. The diluted material must then be thoroughly mixed to
achieve the true dilution.
Example:Dilute a serum sample 1:5 dilution as follow:
Combining 1 unit volume of serum (for example 200 l) + 4 unit volumes of
the saline (for example 800 l)
In this case the dilution factor is 5 (1 + 4 = 5 = dilution factor).
Serial DilutionSerial Dilution A serial dilution is simply a series of simple dilutions which amplifies the
dilution factor quickly beginning with a small initial quantity of material.
The source of dilution material for each step comes from the diluted
material of the previous.
In a serial dilution the total dilution factor at any point is the product of the
individual dilution factors in each step up to it.
Final dilution factor (DF) = DF1 * DF2 * DF3 etc
Example:
Using a primary stock solution (for example 2 mmol/l) prepares a series of different concentrations using serial dilution as follow:
The initial step combines 1 unit volume of stock solution (100 ml) with 9 unit
volumes of distilled water (900 ml) = 1:10 dilution.
Prepare another 6 tubes each one contains 500 ml distilled water
Combines 1 unit volume of the first tube (500 ml) with the 500 ml distilled
water in the second tube
Combines 1 unit volume of the second tube (500 ml) with the 500 ml
distilled water in the third tube and so on until the last tube
The total dilution would be: 1:10 X 2 X 2 X 2 X 2 X 2 X 2 = 1:640
Specific DilutionSpecific Dilution It is used when we need to make a specific volume of known concentration
from stock solutions
To do this we use the following formula:
V1C1=V2C2
V1: the volume of stock we start with. (Unknown)
C1: the concentration of stock solution
V2: total volume needed at the new concentration
C2: the new concentration
Example:Suppose we have 3 ml of a stock solution of 100 mg/ml and we want to make 200 ml of solution having 25 mg/ ml.
V1 = (V2 x C2) / C1
V1 = (0.2 ml x 25 mg/ml) / 100 mg/ml
V1 = 0.05 ml, or 50 ml
So, we would take 0.05 ml stock solution and dilute it with 150 ml of solvent
to get the 200 ml of 25 mg/ ml solution needed
Conversion of Conc. unitsConversion of Conc. units
"X" units
Stock solutions of stable compounds are routinely maintained in labs as more
concentrated solutions that can be diluted to working strength when used in
typical applications. The usual working concentration is denoted as 1X. A
solution 20 times more concentrated would be denoted as 20X and would
require a 1:20 dilution to restore the typical working concentration.
Conversion of Wt% Percent to molarityConversion of Wt% Percent to molarity
Molarity (M) = (% X 10)/Molecular wt
Conversion of molarity to Wt% PercentConversion of molarity to Wt% Percent
Wt% Percent = (M X Molecular wt)/ 10
Conversion of Wt% Percent to normalityConversion of Wt% Percent to normality
Normality (N) = (% X 10)/Equivalent wt
Conversion of normality to Wt% PercentConversion of normality to Wt% Percent
Wt% Percent = (N X Equivalent wt)/ 10
Conversion of Normality to MolarityConversion of Normality to Molarity
Normality (N) = Molarity (M) X n
Conversion of Molarity to NormalityConversion of Molarity to Normality
Molarity (M) = Normality (N) / n
Where n =
number of (H+) in acids or (OH-) in bases or valency in salts
Conversion of Wt% Percent to g/lConversion of Wt% Percent to g/l
Wt% Percent = g/l / 10
Conversion of g/l to Wt% PercentConversion of g/l to Wt% Percent
g/l = Wt% Percent X 10
Conversion of Molarity to g/lConversion of Molarity to g/l
g/l = M X Molecular wt
Conversion of g/l to MolarityConversion of g/l to Molarity
M = Molecular wt / g/l
Conversion of Normality to g/lConversion of Normality to g/l
g/l = M X Equivalent wt
Conversion of g/l to NormalityConversion of g/l to Normality
M = Equivalent wt / g/l
Examples:
1M NaCl 1M NaCl 5.85% NaCl 5.85% NaCl 58.5 g/l NaCl 58.5 g/l NaCl 1N NaCl 1N NaCl
1M HCL 1M HCL 3.09% HCL 3.09% HCL --------------- 1N HCL 1N HCL
0.5M H0.5M H22SOSO44 2.67% H2.67% H22SOSO44 --------------- 1N H1N H22SOSO44
1M NaOH 1M NaOH 4% NaOH 4% NaOH 40 g/l NaOH 40 g/l NaOH 1N NaOH 1N NaOH
0.5M Ca(OH)0.5M Ca(OH)22 3.7% Ca(OH)3.7% Ca(OH)22 37 g/l Ca(OH)37 g/l Ca(OH)22 1N Ca(OH)1N Ca(OH)22
0.5M Na0.5M Na22COCO33 5.29% Na5.29% Na22COCO33 52.99 g/l Nag/l Na22COCO33 1N Na1N Na22COCO33