AP Chemistry Summer Assignment · AP Chemistry Summer Assignment: Briar Woods High School, Ashburn...
Transcript of AP Chemistry Summer Assignment · AP Chemistry Summer Assignment: Briar Woods High School, Ashburn...
AP Chemistry Summer Assignment: Briar Woods High School, Ashburn VA
We are looking forward to teaching you during the 2019-2020 school year! Attached is the summer assignment. The first section is a summary of the information you should have learned in first-year chemistry. After the summary notes, you’ll find several worksheets. These are your homework assignments for the first unit of AP Chemistry. You are expected to have these completed by the third day of class (August 28th or 29th). Your first assessment will evaluate your understanding of the information from the summer assignment. It is important to come to class well prepared.
You are also expected to join the AP Chemistry Summer 2019 Google Classroom. The code is 44ek8r. A copy of the summer assignment packet is posted on Classroom. We will also post EdPuzzle videos during the summer to help you review the first-year chemistry material.
It is recommended that you do not wait until the last minute to start the assignment, do not procrastinate. Remember AP Chemistry is an equivalent course to an Introductory Chemistry college course. Taking a college level course in high school is difficult and it requires commitment, hard work and time.
If you are having difficulty with a specific unit there are many online resources available to you to assist you. You can also post to the forum on Classroom. Please feel free to contact us if you are having difficulty or have any questions.
Have a great summer and enjoy chemistry!
Mrs. Matthews Mr. Smith
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UNIT 00: AP Chemistry Preamble
TOPIC 0A: Chemistry, Scientific Method and Chemical & Physical Change
What is chemistry?
Chemistry can be described as the science that deals with matter, and the changes that matter
undergoes. It is sometimes called the central science because so many naturally occurring
phenomena involve chemistry and chemical change.
Scientific problem solving
Scientific (logical) problem solving involves three steps;
1. State the problem and make observations. Observations can be quantitative (those
involving numbers or measurement) or qualitative (those not involving numbers).
2. Formulate a possible explanation (this is known as a hypothesis).
3. Perform experiments to test the hypothesis. The results and observations from these
experiments lead to the modification of the hypothesis and therefore further
experiments.
Eventually, after several experiments, the hypothesis may graduate to become a theory. A theory
gives a universally accepted explanation of the problem. Of course, theories should be constantly
challenged and may be refined as and when new data and new scientific evidence comes to light.
Theories are different to laws. Laws state what general behavior is observed to occur naturally.
For example, the law of conservation of mass exists since it has been consistently observed that
during all chemical changes mass remains unchanged (i.e., it is neither created nor destroyed).
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States of matter and particle representations
All matter has two distinct characteristics. It has mass and it occupies space. Properties
associated with the three states of matter, and the behaviors of the particles that make up each,
are summarized below.
SOLIDS LIQUIDS GASES
Have a definite shape and
definite volume.
The particles in a solid are
packed tightly together and
only vibrate relatively gently
around fixed positions.
Have no shape of their own
but take the shape of their
container. A liquid has a
definite volume.
The particles in a liquid are
free to move around one
another.
Have neither a definite shape
nor a definite volume.
The particles in a gas spread
apart filling all the space of the
container available to them
and interactions between the
particles are considered to be
negligible.
The circles in the diagrams below represent the relative positions and movements of the particles
in the three states of matter. Expect to see many such particulate representations during the AP
course.
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Physical and chemical changes and properties
All matter exhibits physical and chemical properties by which it can be classified. Examples of
physical properties are color, odor, density, hardness, solubility, melting point, and boiling point.
Chemical properties are those exhibited when a substance reacts with other substances.
Examples of chemical properties are reactions with acids and bases, oxidation and reduction
(REDOX) and a huge number of other chemical reactions. Changes in which the physical or
chemical properties of a substance are altered are considered physical or chemical changes,
respectively.
Physical change
If some aspect of the physical state of matter is altered, but the chemical composition remains the
same, then the change is considered to be a physical change. The most common physical
changes are changes of state. These are summarized below.
SOLID → LIQUID Melting
LIQUID → GAS Boiling
GAS → LIQUID Condensing SOLID → GAS Sublimation
GAS → SOLID Reverse sublimation or deposition
LIQUID → SOLID Freezing
In solids, the particles have relatively little energy and vibrate around fixed positions. If a solid is
heated, the particles gain energy, move around move, and eventually gain enough energy to
break away from their fixed positions and form a liquid. Continued heating leads to the liquid
particles gaining sufficient energy to break away from one another and form a gas. In a gas the
particles move freely and with relatively large amounts of energy.
Chemical change
In a chemical change, which is often called a chemical reaction, the atoms of a substance are
rearranged to form new substances. A chemical change requires that the new substance or
substances formed have a different chemical composition to the original substance or
substances. Chemical changes are often accompanied by observable changes such as color
changes and energy changes.
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There is a very important distinction to be made between these two types of change that you will
encounter in UNIT 2. More on this later, but for now, note the following.
• During physical changes, the intermolecular forces (the forces between particles) are
disrupted, e.g., boiling water separates one water molecule (H2O) from another water
molecule but does not break any, individual water molecule apart.
• During chemical changes the intra forces (the forces within substances) are disrupted,
e.g., during the electrolysis of water, one water molecule (H2O) splits up to form O and H
atoms. Individual water molecules do break apart.
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TOPIC 0B: Measurement
Measurements
Measurements, and subsequently calculations applied to those measurements, allow the
determination of some of the quantitative properties of a substance; for example, mass and
density.
Scientific notation
Measurements and calculations in chemistry often require the use of very large or very small
numbers. In order to make handling them easier, such numbers can be expressed using scientific
notation. All numbers expressed in this manner are represented by a number between 1 and 10
which is then multiplied by 10, raised to a particular power.
The number of places the decimal point has moved determines the power of 10. If the decimal
point has moved to the left then the power is positive, if it has moved to the right then it is
negative.
For example, the number 42000.0 is converted to scientific notation by using the number 4.2. In
the process the decimal point has moved four places to the left, so the power of 10 used is +4.
42000.0 = 4.2 x 104
The number 0.00012 is converted to scientific notation by using the number 1.2. In the process
the decimal point has moved four places to the right, so the power of 10 used is -4.
0.00012 = 1.2 x 10-4
Task 0Bi
1 Convert the following numbers to scientific notation.
(a) 24500
(b) 356
(c) 0.000985
(d) 0.222
(e) 12200
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2. Convert the following scientific notation numbers to non-scientific notation numbers.
(a) 4.2 x 103 (b) 2.15 x 10-4
(c) 3.14 x 10-6
(d) 9.22 x 105
(e) 9.57 x 102
SI units
Units tell us the scale that is being used for measurement. Prefixes are used to make writing very
large or small numbers easier. Common SI (System International) units and prefixes are given
below.
Base quantity Name of unit Symbol
Mass Kilogram kg Length Meter m Time Second s
Amount of substance Mole mol Temperature Kelvin K
Prefix Symbol Meaning Giga G 109 Mega M 106 Kilo k 103 Deci d 10-1 Centi c 10-2 Milli m 10-3
Micro µ 10-6 Nano n 10-9 Pico p 10-12
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Converting units and dimensional analysis (the factor label method)
One unit can be converted to another unit by using a conversion factor. Application of the simple
formula below will allow the conversion of one unit to another. This method of converting between
units is called dimensional analysis or the factor-label method.
(unit a) (conversion factor) = unit b
The conversion factor is derived from the equivalence statement of the two units. For example, in
the equivalence of 1.00 inch = 2.54 cm, the conversion factor will either be,
2.54 cm1.00 inch
or 1.00 inch2.54 cm
The correct choice is the one that allows the cancellation of the unwanted units. For example, to
convert 9.00 inches to cm, perform the following calculation
9.00 inch x
2.54 cm1.00 inch
⎛⎝⎜
⎞⎠⎟
= 22.86 cm
To convert 5.00 cm into inches, perform the following calculation
5.00 cm
x 1.00 inch2.54 cm
⎛⎝⎜
⎞⎠⎟
= 1.97 inches
Task 0Bii
1. Convert the following quantities from one unit to another, using the following
equivalence statements; 1.000 m = 1.094 yd, 1.000 mile = 1760 yd, 1.000 kg = 2.205 lbs
(a) 30 m to miles
(b) 1500 yd to miles (c) 206 miles to m
(d) 34 kg to lbs
(e) 34 lb to kg
2. In each case below, which is the larger quantity?
(a) A distance of 3.00 miles or 3000. m.
(b) A mass of 10.0 kg or 25 lbs.
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Temperature
There are three scales of temperature that you may come across in your study of chemistry. They
are Celsius (oC), Fahrenheit (oF) and Kelvin (K). The following conversion factors will be useful.
Temperature Conversion factors
Celsius to Kelvin
oT in K = T in C + 273
Kelvin to Celsius
oT in C = T in K - 273
Celsius to Fahrenheit
o oT in F = (1.8 (T in C)) + 32
Fahrenheit to Celsius
o
o (T in F - 32)T in C = 1.8
Task 0Biii
1. Convert the following temperatures from one unit to the other.
(a) 263 K to oF
(b) 38 K to oF
(c) 13 oF to oC
(d) 1390 oC to K
(e) 3000 oC to oF
2. When discussing a change in temperature, why will it not matter if the change is
recorded in Celsius or Kelvin?
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Derived units
All other units can be derived from base quantities. One such unit that is very important in
chemistry is volume. Volume has the unit, length3. Common units for volume are liters (L) or
milliliters (mL).
1.000 mL = 1.000 cm3
and
1.000 L = 1000. mL = 1000. cm3 = 1.000 dm3
Density is the ratio of the mass to volume.
volumemassdensity =
This relationship is particularly useful when dealing with liquids in chemistry. Liquids are most
conveniently measured by pouring them into, say, a graduated cylinder. The graduated cylinder
records a volume, not a mass. In order to calculate the mass of a known volume of a liquid
(assuming the density is known) the relationship below can be applied.
mass = (density) (volume)
Assuming that density has the units of g/L, volume has units of L, and by using dimensional
analysis, it can be seen that the resultant unit for mass in this case is g.
( )⎛ ⎞
⎜ ⎟⎝ ⎠
Lg = gL
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Uncertainty, significant figures and rounding
When reading the scale on a piece of laboratory equipment such as a graduated cylinder or a
buret, there is always a degree of uncertainty in the recorded measurement. The reading will
often fall between two divisions on the scale and an estimate must be made in order to record the
final digit. This estimated final digit is said to be uncertain and is reflected in the recording of the
numbers by using +/-. All of the digits that can be recorded with certainty are said to be certain.
The certain and the uncertain numbers taken together are called significant figures.
Determining the number of significant figures present in a number
1. Any non-zero integers are always counted as significant figures.
2. Leading zeros are those that precede all of the non-zero digits and are never counted as
significant figures.
3. Captive zeros are those that fall between non-zero digits and are always counted as
significant figures.
4. Trailing zeros are those at the end of a number and are only significant if the number is
written with a decimal point.
5. Exact numbers have an unlimited number of significant figures. (Exact numbers are those
which are as a result of counting e.g., 3 apples or by definition e.g., 1.000 kg = 2.205 lb).
6. In scientific notation the 10x part of the number is never counted as significant.
Determining the correct number of significant figures to be shown as the result of a
calculation
1. When multiplying or dividing. Limit the answer to the same number of significant figures
that appear in the original data with the fewest number of significant figures.
2. When adding or subtracting. Limit the answer to the same number of decimal places that
appear in the original data with the fewest number of decimal places.
i.e., don’t record a greater degree of significant figures or decimal places in the calculated answer
than the weakest data will allow.
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Rounding
Calculators will often present answers to calculations with many more figures than the significant
ones. As a result many of the figures shown are meaningless, and the answer, before it is
presented, needs to be rounded.
In a multi-step calculation it is possible to leave the rounding until the end i.e., leave all numbers
on the calculator in the intermediate steps, or round to the correct number of figures in each step,
or round to an extra figure in each intermediate step and then round to the correct number of
significant figures at the end of the calculation. In most cases in the AP chemistry course you will
leave numbers on the calculator and round at the end.
Whichever method is being employed, use the simple rule that if the digit directly to the right of
the final significant figure is less that 5 then the preceding digit stays the same, if it is equal to or
greater than 5 then the preceding digit should be increased by one.
Task 0Biv
1. Determine the number of significant figures in the following numbers.
(a) 250.7 (b) 0.00077
(c) 1024
(d) 4.7 x 10-5
(e) 34000000
(f) 1003.
2. Use a calculator to carry out the following calculations and record the answer to the correct number of significant figures.
(a) (34.5) (23.46)
(b) 123 / 3
(c) (2.61 x 10-1) (356)
(d) 21.78 + 45.86
(e) 23.888897 - 11.2
(f) 6 - 3.0
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Accuracy and precision
Accuracy relates to how close the measured value is to the actual value of the quantity. Precision
refers to how close two or more measurements of the same quantity are to one another.
Task 0Bv
1. Consider three sets of data that have been recorded after measuring a piece of wood
that is exactly 6.000 m long.
SET X SET Y SET Z
5.864 m 6.002 m 5.872 m
5.878 m 6.004 m 5.868 m
Average Length 5.871 m 6.003 m 5.870 m
(a) Which set of data is the most accurate?
(b) Which set of data is the most precise?
Percentage error
The data that are derived in experiments will often differ from the accepted, published, actual
value. When this occurs, a common way of expressing accuracy is percentage error.
( )Actual Value - Calculated ValuePercentage Error = x 100
Actual Value
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TOPIC 0C: Atomic Theory
Brief history of atomic theory
Circa. 400-5 BC. Greek philosopher Democritus proposes the idea of matter being made up of
small, indivisible particles (atomos).
Late 18th Century. Lavoisier proposes the Law of conservation of mass and Proust proposes the
Law of constant composition.
Early 19th Century. Using the previously unconnected ideas above, John Dalton formulates his
Atomic Theory.
Dalton’s atomic theory
1. Elements are made from tiny particles called atoms.
2. All atoms of a given element are identical (N.B., see isotopes).
3. The atoms of a given element are different to those of any other element.
4. Atoms of different elements combine to form compounds. A given compound always has
the same relative numbers and types of atoms. (Law of constant composition).
5. Atoms cannot be created or destroyed in a chemical reaction they are simply rearranged
to form new compounds. (Law of conservation of mass).
Structure of the atom and the periodic table
Several experiments were being carried out in the 19th and 20th centuries that began to identify
the sub-atomic particles that make up the atom. A summary of those experiments is given below.
Scientist Experiment Knowledge gained Relating to
Crookes Cathode Ray Tube Negative particles of some kind exist Electron
J. J. Thomson Cathode Ray Deflection
Mass/charge ratio of the electron determined
Electron
Millikan Oil Drop Experiment Charge on the electron Electron
Rutherford, Marsden and Geiger Gold Foil Experiment Nucleus present in
atom The nucleus of an
atom and the proton
In the first part of the 20th Century, Bohr built upon Rutherford’s idea by introducing quantum
theory to the Solar System Model, and proposed the idea that the atom was made up of a
LO 1.13
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nucleus containing protons, that was being orbited by electrons, but only in specific, allowed
orbits. Schrödinger subsequently expanded upon Bohr’s model, in order to incorporate the wave
nature of the electrons. Once Chadwick’s discovered the neutron in 1932, the modern picture of
the atom in its simplest form was complete.
Particle Charge Mass in atomic mass units (amu) Position in atom
PROTON +1 1 Nucleus
NEUTRON 0 1 Nucleus
ELECTRON -1 11836
Outside of the nucleus
The atomic numbers (in the periodic table below shown above the element symbol and
sometimes referred to as Z) and mass numbers (in the periodic table below shown below the
symbol and sometimes referred to as A) have specific meanings.
Atomic number = the number of protons in the nucleus of one atom of the element
Since all atoms are neutral it also tells us the number of electrons surrounding the nucleus.
N.B., when atoms lose or gain electrons the proton and electron numbers become unbalanced
and the atoms become charged particles, i.e., they are no longer neutral. These charged particles
are called ions. A negative ion is formed when an atom gains electrons to possess a greater
number of electrons than protons, and is called an anion. A positive ion is formed when an atom
loses electrons to possess a fewer number of electrons than protons, and is called a cation.
Mass number = the number of protons + the number of neutrons in one atom of the element
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Period GROUP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
1 1 H 1
2 He 4
2 3 Li 7
4 Be 9
T R A N S I T I O N M E T A L S
5 B 11
6 C 12
7 N 14
8 O 16
9 F 19
10 Ne 20
3 11 Na 23
12 Mg 24
13 Al 27
14 Si 28
15 P 31
16 S 32
17 Cl
35.5
18 Ar 36
4 19 K 39
20 Ca 40
21 Sc 45
22 Ti 48
23 V 51
24 Cr 52
25 Mn 55
26 Fe 56
27 Co 59
28 Ni 59
29 Cu 64
30 Zn 65
31 Ga 70
32 Ge 73
33 As 75
34 Se 79
35 Br 80
36 Kr 84
5 37 Rb 86
38 Sr 88
39 Y 89
40 Zr 91
41 Nb 93
42 Mo 96
43 Tc 99
44 Ru 101
45 Rh 103
46 Pd 106
47 Ag 108
48 Cd 112
49 In
115
50 Sn 119
51 Sb 122
52 Te 128
53 I
127
54 Xe 131
6 55 Cs 133
56 Ba 137
57 La* 139
72 Hf
178
73 Ta 181
74 W
184
75 Re 186
76 Os 190
77 Ir
192
78 Pt
195
79 Au 197
80 Hg 201
81 Tl
204
82 Pb 207
83 Bi
209
84 Po 210
85 At
210
86 Rn 222
7 87 Fr
223
88 Ra 226
89 Ac† 226
104 Rf
105 Db
106 Sg
107 Bh
108 Hs
109 Mt
110 Ds
111 Rg
112 Cn
113 Nh
114 Fl
115 Mc
116 Lv
117 Ts
118 Og
*Lanthanides 58 Ce 140
59 Pr
141
60 Nd 144
61 Pm 147
62 Sm 150
63 Eu 152
64 Gd 157
65 Tb 159
66 Dy 163
67 Ho 165
68 Er
167
69 Tm 169
70 Yb 173
71 Lu
175
†Actinides 90 Th 232
91 Pa 231
92 U
238
93 Np 237
94 Pu 242
95 Am 243
96 Cm 247
97 Bk 251
98 Cf
251
99 Es 254
100 Fm 253
101 Md 256
102 No 254
103 Lr
257
KEY:
Metal Semi Metal Non-metal
13 Al 27
14 Si 28
15 P 31
In this example Al is a metal, Si is a semi-metal (metalloid) and P is a non-metal.
Task 0Ci
1. Determine the number of protons, electrons and neutrons in,
(a) 210Pb82
(b) 34S16
2. Using only the periodic table above, determine how many elements within the first 20,
have atoms with;
(a) The same numbers of protons and electrons (b) The same numbers of protons and neutrons
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TOPIC 0D: Nomenclature
Nomenclature
Nomenclature is the language of chemistry, and a grasp of it is essential to studying the subject.
Symbols
Each element has a symbol displayed on the periodic table. Some elements have a symbol that
is a single letter while others have a symbol made up of two letters. It is important when writing
the two letter symbols to ensure that you use a lower case letter for the second letter. This may
sound trivial but is very important, for example, Co (cobalt), a metal element, is not the same as
CO (carbon monoxide), a gaseous compound made from carbon (C) and oxygen (O).
Binary compounds of metals and non-metals (ionic compounds)
Binary compounds are those formed between only two elements. In compounds where one is a
metal and one a non-metal an ionic compound is formed. An ion is a charged particle and ionic
formulae and names can be determined by considering the charge on the ions. To find the
formula of an ionic compound the positive and negative charges must be balanced, i.e., there
must be no net charge.
To name a binary compound of a metal and a non-metal, the unmodified name of the positive ion
is written first followed by the root of the negative ion with the ending modified to -ide. For
example, NaCl is sodium chloride.
A few common ions, their charges and formulae are listed below.
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Negative ions (ANIONS) Positive ions (CATIONS)
Name Charge Symbol Name Charge Symbol
Bromide 1- Br- Aluminum 3+ Al3+
Chloride 1- Cl- Barium 2+ Ba2+
Fluoride 1- F- Calcium 2+ Ca2+
Hydride 1- H- Copper (I) 1+ Cu+
Iodide 1- I- Copper (II) 2+ Cu2+
Nitride 3- N3- Hydrogen 1+ H+
Oxide 2- O2- Iron (II) 2+ Fe2+
Phosphide 3- P3- Iron (III) 3+ Fe3+
Sulfide 2- S2- Lead (II) 2+ Pb2+
Lead (IV) 4+ Pb4+
Lithium 1+ Li+
Magnesium 2+ Mg2+
Manganese (II) 2+ Mn2+
Nickel (II) 2+ Ni2+
Potassium 1+ K+
Silver 1+ Ag+
Sodium 1+ Na+
Strontium 2+ Sr2+
Tin (II) 2+ Sn2+
Tin (IV) 4+ Sn4+
Zinc 2+ Zn2+
Most transition metal ions (and a few other metal ions) include a Roman numeral after the name,
for example, copper (II). These metals form ions with varying charges, and the Roman numeral
identifies the charge in each case. Elements that commonly form an ion with only a single charge
for example, sodium, do not have Roman numerals associated with them.
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Task 0Di
1. Name these binary compounds.
(a) NaCl
(b) SrO
(c) AlN
(d) BaCl2(e) K2O
(f) CuO
(g) Cu2O
2. Convert these names to formulae.
(a) Magnesium nitride
(b) Barium bromide
(c) Aluminum phosphide
(d) Potassium iodide
(e) Lithium chloride
(f) Sodium fluoride(g) Tin (IV) bromide
Binary acids
Acids will be discussed at great length later in the course, but for the purposes of nomenclature,
an acid can be defined as a compound that produces hydrogen ions (H+) when it is dissolved in
water, and the formulae of acids start with ‘H’. Binary acids are formed when hydrogen ions
combine with monatomic anions.
To name a binary acid use the prefix ‘hydro’ followed by the other non-metal name modified to an
–ic ending. Then add the word ‘acid’. For example, HCl is hydrochloric acid.
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Polyatomic ions
Polyatomic ions are those where more than one element are combined together to create a
species with a charge. Some of these ions can be named systematically, others names must be
learned. Some common polyatomic ions, their charges and formulae are listed below.
Common Polyatomic ions Name Charge Formula
Ammonium 1+ NH4+
Carbonate 2- CO32-
Chromate (VI) 2- CrO42-
Dichromate (VI) 2- Cr2O72-
Ethanedioate 2- C2O42-
Hydrogen carbonate 1- HCO3-
Hydrogen sulfate 1- HSO4-
Hydroxide 1- OH- Manganate (VII) (permanganate) 1- MnO4
- Nitrate 1- NO3
- Nitrite 1- NO2
- Phosphate 3- PO4
3- Sulfate 2- SO4
2- Sulfite 2- SO3
2-
Polyatomic anions where oxygen is combined with another non-metal are called oxoanions and
can be named systematically. In these oxoanions certain non-metals (Cl, N, P and S) form a
series of oxoanions containing different numbers of oxygen atoms. Their names are related to the
number of oxygen atoms present, and are based upon the system below.
Name Number of oxygen atoms
Hypo(element)ite q
Increase in number of oxygen atoms
q
(element)ite
(element)ate
Per(element)ate
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Where there are only two members in such a series the endings are –ite and –ate. For example,
sulfite (SO32-) and sulfate (SO4
2-). When there are four members in the series the hypo- and per-
prefixes are used additionally.
Some oxoanions contain hydrogen and are named accordingly, for example, HPO42-, hydrogen
phosphate. The prefix thio- means that a sulfur atom has replaced an atom of oxygen in an anion.
To name an ionic compound that contains a polyatomic ion, the unmodified name of the positive
ion is written first followed by unmodified name of the negative ion. For example, K2CO3 is
potassium carbonate.
Oxoacids
Oxoacids are formed when hydrogen ions combine with polyatomic oxoanions. This gives a
combination of hydrogen, oxygen and another non-metal.
To name an oxoacid use the name of the oxoanion and replace the -ite ending with –ous or the -
ate ending with -ic. Then add the word ‘acid’. For example, H2SO4 is sulfuric acid.
To illustrate the names of these oxoanions and oxoacids consider the following example
using chlorine as the non-metal.
Formula and name of oxoacid Formula and name of corresponding oxoanion HClO Hypochlorous acid ClO- Hypochlorite HClO2 Chlorous acid ClO2
- Chlorite HClO3 Chloric acid ClO3
- Chlorate HClO4 Perchloric acid ClO4
- Perchlorate
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Task 0Dii
1. What are the formulae for the following ionic compounds?
(a) Ammonium nitrate
(b) Copper (II) bromide
(c) Copper (I) bromide
(d) Zinc hydrogen sulfate
(e) Aluminum sulfate
(f) Sodium perchlorate
(g) Copper (II) iodite
2. Convert the following formulae to names.
(a) NaNO3
(b) KMnO4
(c) CaC2O4
(d) CuSO4
(e) Cu2SO4
(f) KNO2
(g) LiClO4
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Binary compounds of two non-metals (molecular compounds)
If the two elements in a binary compound are non-metals, then the compound is molecular.
To name a molecular compound of two non-metals, the unmodified name of the first element is
followed by the root of the second element with ending modified to -ide. In order to distinguish
between several different compounds with the same elements present use the prefixes mono, di,
tri, tetra, penta and hexa to represent one, two, three, four, five and six atoms of the element
respectively. For example, SO2 is sulfur dioxide.
Some other examples are given below.
Formula Name BCl3 Boron trichloride CCl4 Carbon tetrachloride CO Carbon monoxide CO2 Carbon dioxide NO Nitrogen monoxide NO2 Nitrogen dioxide
Note that the prefix mono is only applied to the second element present in such compounds, if the
prefix ends with ‘a’ or ‘o’, and the element name begins with ‘a’ or ‘o’, then the final vowel of the
prefix is often omitted.
Some compounds have trivial names that have come to supersede their systematic names, for
example, H2O is usually ‘water’, not dihydrogen monoxide!
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Task 0Diii
1. Write formula or names for the following molecular compounds.
(a) Dinitrogen tetroxide
(b) Phosphorous pentachloride
(c) Iodine trifluoride
(d) Nitrogen dioxide
(e) Dihydrogen monoxide
2. Convert the following formulae to names.
(a) N2O5
(b) PCl3(c) SF6
(d) H2O
(e) Cl2O
Hydrates
Hydrates are ionic formula units with water molecules associated with them. The water molecules
are incorporated into the solid structure of the ions. Strong heating can generally drive off the
water in these salts. Once the water has been removed the salts are said to be anhydrous
(without water).
To name a hydrate use the normal name of the ionic compound followed by the term ‘hydrate’
with an appropriate prefix to show the number of water molecules per ionic formula unit. For
example, CuSO4.5H2O is copper (II) sulfate pentahydrate.
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Formulae of compounds
The chemical formula of a compound shows the exact ratio of the different elements that are
present. The numbers of each element are recorded using a subscript to the right of the elements
symbol. When only one atom is present, the subscript one is assumed (understood), and not
written.
Percentage composition in chemical formula
To determine the % composition of an individual element within a compound, simply express the
mass of each element as a % of the mass of the compound.
Empirical formulae
The empirical formula is the simplest whole number ratio of the atoms of each element in that
compound and can be calculated from mass data. There is a simple method to follow.
Take the percentage of each element present, assume a sample of 100 g, and divide that
mass by the appropriate mass number. (This gives the number of moles - see later).
Find the smallest number calculated in and divide all the results of the calculations in by
that number. (This gives the molar ratio). N.B. Avoid rounding up or down too much at this stage
and be lenient with significant figures.
The results from should be in a convenient ratio and give the empirical formula. N.B. It may
be that the ratio includes a decimal (fraction) such as .500, .250 or .333 etc. If so then multiply all
numbers by 2, 4 or 3 as appropriate to remove the decimal.
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For example; calculate the empirical formula for the compound containing 40.1% carbon, 6.60%
hydrogen and 53.3% oxygen.
C H O Assuming 100g
sample, the % by mass 40.1 6.60 53.3
RAM (from periodic table)
12.011 1.0079 16.00
% by mass ÷ RAM 3.34 6.55 3.33
divide by smallest 1 2 1
Empirical formula C1H2O1 or CH2O
Task 04a
1. Calculate the empirical formulae of the three oxides of iron shown below.
(a) 77.78% Fe, 22.22% O
(b) 70.00% Fe, 30.00% O
(c) 72.40% Fe, 27.60% O
2. A hydrocarbon (a compound containing only hydrogen & carbon) is found to be
7.690% H and 92.31% C by mass. Calculate its empirical formula.
Formulae of Molecules - Molecular formulae
Once the empirical formula has been established, and given further appropriate data, the
molecular formula can be calculated. The molecular formula tells us exactly how many atoms of
each element are present in the compound rather than just the simplest whole number ratio. It is
a simple multiple of the empirical formula. Hence, in the example of an empirical formula of
CH2O, the molecular formula could be C2H4O2 or C3H6O3 etc. To find the molecular formula it is
necessary to know the Molar mass or Relative Molecular Mass (RMM). Given the RMM to be 60
g mol-1
it is clear the molecular formula is C2H4O2, i.e., twice the empirical.
Task 04b
The same compound as in question #2 in Task 4a has a molar mass of 78.00 g mol-1
. What
is the molecular formula of the compound?
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Chemical equations
Chemical equations are a shorthand method used to illustrate what happens during a chemical
reaction. There are a number of steps to writing an equation.
1. Write down the equation in words.
2. Fill in the correct formulae for all the substances.
3. Balance the equation. Balancing the equation can be tricky and requires practice. It involves
the following steps.
I. Ensure the correct formulae are being used for all the reactants and products
II. Balance each element in turn remembering to multiply brackets out carefully. This
process in rather unscientific and is essentially a process of trial and error but can be
helped by the following tips;
If an element appears in only one compound on each side of the equation, try balancing that first.
Secondly, if one of the reactants or products appears as the free element, try balancing that last.
III. When balancing, only place numbers in front of whole formulae. Do not change the
(correct) formulae of any of the reactants or products, or add any extra formulae. The
numbers that appear in front of each formula are called the stoichiometric coefficients.
They have an extremely important role to play in calculations since they give the
reacting ratio (i.e. the number of moles of one substance that react with, or are produced
from, others).
4. Add state symbols, (s) for solid, (l) for liquid, (g) for gas and (aq) for aqueous meaning in
solution with water.
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Task 04c
1. Write balanced equations for the following reactions.
(a) Hydrogen + Copper (II) oxide Copper + Water
(b) Carbon + Oxygen Carbon monoxide
(c) Magnesium + Sulfuric acid Hydrogen + Magnesium Sulfate
2. Balance the following equations.
(a) Ca + H2O H2 + Ca(OH)2
(b) Cu + O2 CuO
(c) Na + O2 Na2O
(d) Fe + HCl FeCl2 + H2
(e) Fe + Br2 FeBr3
(f) C4H8 + O2 CO2 + H2O
(g) Na2CO3 + HI NaI + CO2 + H2O
(h) CuCO3 CuO + CO2
(i) Pb(NO3)2 PbO + NO2 + O2
(j) H2SO4 + KOH K2SO4 + H2O
(k) NaHCO3 Na2CO3 + H2O + CO2
(l) Al + O2 Al2O3
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The mole concept and calculations from equations
Atomic Mass Units
We have seen previously how atoms are comprised of protons, neutrons and electrons and how
the protons and neutrons have masses of approx. 1 atomic mass unit (amu) respectively and that
electrons do not contribute significantly to the mass. If we define the amu as having a mass of
1.66 x 10-24
g we can see that atoms are extremely small and have an extremely small mass.
For example, 1 atom of Cl35
contains 17 protons and 18 neutrons. This is a total of 35 amu
(ignoring the electrons) and has a mass of 5.81 x 10-23
g. This is a very small number so we use
the concept of the mole (see below) to overcome the problem of handling such small quantities.
As you will see 1 mole contains 6.022 x 1023
particles. So if we take 1 mole of Cl35
atoms they will
have a mass of (5.81 x 10-23
g) (6.022 x 1023
) = 35.0 g.
Relative Atomic Mass (RAM) or Molar Mass
RAM is defined as the weighted average of the masses of all the atoms in a normal isotopic
sample of the element based upon the scale where 1 mole of atoms of the C12
isotope has a
mass of exactly 12.00 g.
We have seen previously how elements occur in nature as a number of different isotopes an as a
result they have a RAM that is not an integer. For example, chlorine occurs in nature as approx.
75% Cl 35
and 25% Cl 37
Average Relative Atomic Mass of 1 mole of chlorine atoms =
100
25 x 3775 x 35 = 35.5 g
Average relative atomic masses are the mass numbers recorded on the periodic table. The
relative masses of atoms shown on the periodic table can be used to determine the relative
masses of molecules and ions by simple summation.
Relative Molecular Mass (RMM) or Molar Mass - Found by adding all of the individual RAM’s
together in one molecule of a compound.
Relative Formula Mass (RFM) or Molar Mass - Found by adding all of the individual RAM’s
together in one formula unit of an ionic compound.
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Avogadro’s number and the mole concept
In chemistry, amounts of substances are measured in moles (mols). The mole is a standard
number of particles (atoms, ions or molecules) and can be defined as, the amount of any
substance that contains the same number of particles, as there are C12
atoms in 12.00g of the C12
isotope. The actual number of particles in a mole, known as the Avogadro constant or number is
found to be 6.022 x 1023
particles per mole and has the unit, mol-1
. For example, one mole of
atoms = 6.02 x 1023
atoms.
The average Relative Atomic Mass (RAM) of each element is given on the periodic table. The
figure shows the average mass of one mole of atoms of that particular element. This leads to the
relationships below.
mass of sample mass of sampleNumber of Moles of an Element
RAM Molar Mass
mass of sample mass of sampleNumber of Moles of a Molecular compound =
RMM Molar Mass
mass of sample mass of sampleNumber of Moles of an Ionic compound
RFM Molar Mass
Task 04d
1. What is the mass of one mole of sodium chloride, NaCI
2. How many moles of Ca atoms are there in 140. g of calcium?
3. How many moles of CuBr2 are there in 0.522 g of copper(II) bromide?
4. How many moles of CO2 molecules are there in 23.0 g of carbon dioxide?
5. How many ‘particles’ are present in each of the chemicals in questions #1-4 above?
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If we know the number of moles of a substance that is present in a reaction and we know a
balanced chemical equation, (i.e. we know the reacting ratio), it is possible to calculate the moles
of another substance present in the equation. Use this method;
1. Write a correct and balanced equation.
2. Find the number of moles present by using a moles relationship for one substance.
3. Use the stoichiometric coefficients in the equation to find the reacting ratio of the moles. Use
this relationship to find the number of moles of the unknown substance.
4. Re-apply a moles relationship for the unknown substance.
Task 04e
The combustion of methane (CH4) can be summarized by the equation below.
CH4 + 2O2 CO2 + 2H2O
1. Calculate the mass of O2 required to produce 2.23 g of carbon dioxide.
2. Calculate the mass of water produced when 34.0 g of CH4 is burned.
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Volumetric analysis and moles
Chemical reactions are often carried out between substances that are in solution (dissolved in a
solvent, usually water). The concentration of a solution can be measured in terms of the number
of grams of the solute (solid) that has been dissolved in a particular volume of the solution (where
water is usually the solvent), or more usually, in terms of the number of moles of the solute in a
particular volume of the solution. Typical units are g dm-3
or g/dm3 or mol dm
-3 or mol/dm
3 or
mol/L or mol L-1
.
The method of expressing the concentration of a solution in mol L-1
is the most common (and
most useful) and is referred to as Molarity (M). So, for example, a solution that has a
concentration of 0.250 mol L-1
can be referred to as 0.250 M solution, or a 0.250 “molar” solution.
When concentration is measured in mol L-1
, or M, and volume in L, then, for solutions;
Moles (concentration) (volume)
Task 04f
1. What mass of solute (solid sodium carbonate) must be used in order to prepare 275
mL of 1.20 mol L-1
sodium carbonate solution?
2. A sample of copper (II) sulfate pentahydrate with a mass of 8.512 g is dissolved in
500.0 mL of water. A 25.00 mL portion completely reacts with 20.00 mL of a 0.1702 mol
L-1
solution of iodide ions. In what molar ratio do Cu2+
and iodide ions react?
Questions #3-5 require balanced equations before they can be solved.
3. Carbonates, in the form of antacid tablets, can be used to neutralize stomach acid. 25.0
mL of 0.100 mol L-1
sodium carbonate solution completely reacts with 35.3 mL of HCl
in such a simulated neutralization. What is the concentration (molarity) of the acid?
4. Some metals will react vigorously with acids to produce hydrogen gas. What mass of
zinc metal, will react completely with 75.0 mL of 0.200 mol L-1
sulfuric acid?
5. Hydroxides can be used to neutralize acids. What volume of 1.00 mol L-1
NaOH, would
be required to completely neutralize 25.0 mL of 2.00 mol L-1
HCI?
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Dilution
Often, solutions are prepared by adding water to (diluting) more concentrated ones. For example,
if 4.0 L of a 2.0 M solution was required, it could be made by diluting some 10. M solution.
Calculations involving dilution problems involve three steps.
1. Calculate the number of moles present in the final, diluted solution, by applying moles =
(concentration) (volume).
2. Calculate the volume of the starting, more concentrated solution that supplies this
number of moles by applying moles = (concentration) (volume).
3. The volume of water that must be added to the concentrated solution is simply the
difference between the volume of the final, diluted solution and the volume of the
concentrated solution.
Worked Example
Calculate the volume of water that must be added to prepare 2.0 L of 3.0 M KOH from a stock
solution that has a concentration of 8.0 mol L-1
.
1. Final solution must contain (2.0 L)(3 mol/L) mols = 6.0 mols of KOH.
2. Since moles = (concentration) (volume), the volume (in L) of the stock (concentrated)
solution that contains 6.0 mols of KOH = 6.0 mol
8.0 mol/L = 0.75 L.
3. So, by taking 0.75 L of the stock solution and adding 1.25 L of water to make the solution
up to 2.00 L, the final, diluted solution, will have a concentration (molarity) = 6.0 mol
2.0 L =
3.0 mol L-1
or 3.0 M.
Task 04g
1. Calculate the volume of 3.25 M nitric acid that must be diluted with water to produce
500. mL of 1.25 M nitric acid.
2. Calculate the volume of 2.60 M KOH that must be diluted with water to produce 250.
mL of 2.00 M KOH.
3. What volume of water must be added to 4.0 M HCl in order to produce 2.0 L of 0.5 M
HCl?
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Combustion Analysis
Compounds that contain carbon and hydrogen only, when burned completely in oxygen, will yield
only carbon dioxide and water. Analysis of the mass of CO2 and H2O produced can be used to
determine the empirical formula of the substance in question. This method assumes that all the
carbon in CO2 originated from the carbon in the original compound, and all the hydrogen in the
water originated from the hydrogen in the original compound. The method is as follows.
1. Calculate the moles of CO2 produced. Since there is one carbon atom in one molecule of
CO2 this is also the number of moles of C atoms present in the original compound.
2. Calculate the moles of H2O produced. Since there are two hydrogen atoms in one
molecule of H2O multiply this number by two to calculate the number of moles of H atoms
present in the original compound.
3. Calculate the mass of C and H present in the combusted sample by multiplying the moles
of each by their RAM’s.
4. If there is another element present (typically O) in the combusted substance then
calculate its mass by subtracting the mass of C and H from the total mass of the
combusted sample. Turn this mass into moles by dividing by the appropriate RAM.
Find the smallest number of moles calculated and divide all the numbers of moles by that
number. (This gives the molar ratio). N.B. Avoid rounding up or down too much at this
stage and be lenient with significant figures.
5. The results from #4 should be in a convenient ratio and give the empirical formula. N.B. It
may be that the ratio includes a fraction such as .500, .250 or .333 etc. If so then multiply
all numbers by 2, 4 or 3 as appropriate to remove the fraction.
6. If necessary use the Molar Mass to turn the empirical formula into a molecular formula.
Task 04h
When 4-ketopentenoic acid is analyzed by combustion, it is found that a 0.3000 g sample
produces 0.579 g of CO2 and 0.142 g of H2O. The acid contains only carbon, hydrogen, and
oxygen. What is the empirical formula of the acid?
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Analysis of hydrates
Hydrates are formula units with water associated with them. The water molecules are
incorporated into the solid structure. For example, CuSO4.5H2O, copper(II) sulfate pentahydrate.
Strong heating can evaporate the water. When water is removed the salts are called anhydrous
(without water).
Task 04i
1. A sample of the hydrated salt CoCl2.xH2O, with a mass of 11.73 g is weighed, heated to
drive off the water of crystallization, cooled and reweighed until constant mass (6.410
g) is achieved. Calculate the value of x.
2. What is meant by the term, “constant mass” in question #1?
Limiting Reactant
When all the reactants in a chemical reaction are completely consumed, i.e. they are all
converted to products, then the reactants are said to be in stoichiometric proportions. On other
occasions it may be necessary to ensure that only one particular reactant is completely used up.
This is achieved by using an excess of all the other reactants. The reactant that is completely
consumed is called the limiting reagent and it, is what determines the quantities of products that
form.
Task 04j
The two non-metals, sulfur and chlorine, react according to the equation below.
S(s) + 3Cl2(g) SCl6(l)
If 202 g of Sulfur are allowed to react with 303 g of CI2 in the reaction above, which is the
limiting reactant, how much product will be produced and what mass of the excess
reactant will be left over?
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Percentage yield
In all chemical syntheses the yield of the product will be less than 100%. The % yield is given as
actual yield of product% Yield = X 100
theoretical yield of product
The yield is usually less than 100% since the reactants are often not pure, some of the product is
lost during purification, the reaction may be reversible and/or side reactions may give by-
products.
Task 04k
Aluminum will react with oxygen gas according to the equation below;
4Al + 3O2 2Al2O3
In one such reaction, 23.4 g of Al are allowed to burn in excess oxygen. 39.3 g of
aluminum oxide are formed. What is the percentage yield?
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AP WORKSHEET 00a: Significant Figures 1. Determine the number of significant figures in each of the following. (6) (a) 0.7680 (b) 1230.00 (c) 1000.01 (d) 120.0 (e) 1.09 x 10
4
(f) 0.0080060 2. Use a calculator to find the results of the following and then round the answer to the correct
number of significant figures. (6)
(a) 34.66 + 333.0 (b) 1.23 + 9.66 (c) 445 - 1.22 (d) 18.2 + 1.998 (e) 10.2 – 1.34 (f) 100 - 23 3. State the significant figure rule that is associated with “captive zeros”. (1) 4. State the significant figure rule that is associated with “leading zeros”. (1) 5. State the significant figure rule that is associated with “trailing zeros”. (1) 6. State the significant figure rule that is associated with addition and subtraction operations. (1) 7. State the significant figure rule that is associated with multiplication and division operations.
(1)
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8. Use a calculator to find the results of the following calculations and then round the answer to
the correct number of significant figures. (6)
(a) 12 x 11.45 (b) (1.23 x 10
3) x (6.4 x 10
2)
(c) 5.233 x 6.324 (d) 34 / 22 (e) (1.8 x 10
5) / 14
(f) 100.23 / 5.22 9. Round each of the following to three significant figures. (6) (a) 167.789 (b) 0.0000456922 (c) 23.00567 (d) 3.4569 (e) 7903.0005 (f) 11.044 10. How many significant figures in each of the following? (6) (a) 654.001 nm (b) 6.02 x 10
23 particles
(c) 1.0079 g (d) 13 neutrons (e) 11.22201 mg (f) 0.004504 g
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AP WORKSHEET 00b: Unit Conversions This worksheet utilizes the conversions given at this web site http://www.onlineconversion.com 1. Perform the following conversions. In each case show the full, dimensional analysis. Source
any conversion factors from the web site above. An example is given below. (6)
Question: 3.00 cm to mm.
Answer: 3.00 cm
10 mm
1 cm
= 30 mm
(a) 120 J to MJ (b) 3 m to cm (c) 400 miles to km (d) 25 hectares to acres (e) 34 inches to ft (f) 289 s to hrs 2. Perform the following conversions. In each case you do NOT need to show the full,
dimensional analysis. Source any conversion factors from the web site above. (6)
(a) 120000 J to kJ (b) 13 kg to lbs (c) 83.2 K to
oC
(d) 48 mins to ms (e) 34
oF to
oC
(f) 13.2 kg to lbs
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2
3. Perform the following sequences of conversions. In each case show the full, dimensional
analysis. Source any conversion factors from the web site above. An example is given below.
(6)
Question: 3.00 cm to m VIA mm.
Answer: 3.00 cm
10 mm
1 cm
0.001 m
1 mm
= 0.03 m
(a) 679 nm to cm VIA m (b) 23 miles to m VIA km (c) 567 feet to m VIA yd (d) 12 L to UK gal VIA mL (e) 8 MJ to J VIA kJ (f) 418 s to hrs VIA min
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1
AP WORKSHEET 00c: Atomic Structure & Ions Use the periodic table here; http://www.adriandingleschemistrypages.com/apptable.pdf to help you answer this worksheet. 1. What is the charge on a sodium atom? (1) 2. What is the charge on a sodium nucleus? (1) 3. What is the atomic number of potassium? (1) 4. How many protons are there in the nucleus of a potassium atom? (1) 5. How many electrons in the potassium nucleus? (1) 6. What is the most likely charge (the most common charge) on an ion of sulfur? (1) 7. If a chloride ion and a strontium ion were to form a compound, what would its formula be? (1) 8. What do all the ions of the transition metals have in common with one another? (1)
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AP WORKSHEET 00d: Elements & Symbols Although you will always have access to a periodic table in tests and exams, the periodic table will NOT have element names on it. In that light it will be extremely helpful to you if you can begin to recognize as many of the element names and symbols as possible.
1. Assign the 50 elements below to one of the four lists based upon their symbols. (50) List A: Elements that have symbols that are only the first letter of the element's name List B: Elements that have symbols that are the first two letters of the element's name List C: Elements that have symbols that are the first letter and another letter of the element’s name List D: Elements that have symbols that are rooted in another language or other source
ELEMENT NAME ELEMENT SYMBOL LIST A, B, C or D?
aluminum
antimony
argon
arsenic
barium
beryllium
bismuth
boron
bromine
cadmium
calcium
carbon
cerium
cesium
chlorine
chromium
cobalt
copper
fluorine
gallium
gold
helium
hydrogen
iodine
iron
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ELEMENT NAME ELEMENT SYMBOL LIST A, B, C or D?
lead
lithium
magnesium
manganese
mercury
neon
nickel
oxygen
phosphorus
platinum
potassium
radium
selenium
silicon
silver
sodium
strontium
sulfur
tin
titanium
tungsten
uranium
vanadium
xenon
zinc 2. Using the periodic table, find one more (i.e. not those listed in question #1.) element for each
list. (4) A. _______________
B. _______________ C. _______________ D. _______________
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AP WORKSHEET 00e: Inorganic Nomenclature I 1. The following compounds are all binary compounds. Give the name of each one. (6)
(a) SrO (b) K2O (c) Na2S (d) Cs3P (e) AlCl3 (f) Mg3N2
2. Some of the following name and formula combinations are incorrect. Identify the correct combinations. For the others, suggest corrected combinations. (13)
(a) barium hydroxide, BaOH2 (b) sodium oxide, SoO2 (c) barium chloride, BCl3 (d) strontium oxide SrO2 (e) boron trifluoride, BoFl6 (f) vanadium (III) chloride, VCl3 (g) magnesium oxide, MgO4
3. Write the name of the following compounds. Use Roman numerals in the names. (7) (a) FeI3 (b) MnCl2 (c) HgO
(d) Cu2S (e) CuS (f) SnI4 (g) MnBr2
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4. Write the name of each of the following. To help get the correct name, use the periodic table to determine which elements are metals, which are non-metals and which compounds should include Roman numerals in their names. (16) (a) N2Br5 (b) P2S5 (c) Ge2O3 (d) N2O5 (e) SiO2 (f) AlH3 (g) FeO (h) CuCl2 (i) OCl2 (j) XeF6 (k) RaCl2 (l) SeCl2 (m) PCl5 (n) Na3P (o) CuF (p) V2O5
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AP WORKSHEET 00f: Inorganic Nomenclature II Add either a name or a formula to complete each table. (100)
1. Potassium dichromate
2. Lithium sulfide
3. Potassium bromide
4. Cesium iodide
5. Calcium phosphide
6. Sodium fluoride
7. Strontium oxide
8. Beryllium sulfide
9. Magnesium bromide
10. Lithium oxide
11. Strontium chloride
12. Barium bromide
13. Magnesium sulfide
14. Magnesium iodide
15. Hydrogen fluoride (Hydrogen monofluoride)
16. Barium phosphide
17. Sodium hydrogen phosphate
18. Potassium chloride
19. Lithium nitride
20. Calcium sulfide
21. Rubidium oxide
22. Strontium nitride
23. Cesium phosphide
24. Magnesium carbonate
25. Beryllium sulfate
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26. Dinitrogen Tetraoxide
27. Carbon dioxide
28. Mercury(I) chloride
29. Hydroiodic acid
30. Iodic acid
31. Perbromic acid
32. Hypobromous acid
33. Phosphorus pentachloride
34. Iodine monochloride
35. Antimony(III) fluoride
36. Bromine monofluoride
37. Bromine dioxide
38. Dinitrogen pentoxide
39. Carbon monosulfide
40. Tellurium dioxide
41. Phosphorus tribromide
42. Carbon tetraiodide
43. Vanadium(V) chromate
44. Zinc carbonate
45. Silver hydroxide
46. Vanadium(III) chromate
47. Mercury(II) iodide
48. Uranium(V) nitrate
49. Nickel (III) nitride
50. Sulfuric acid
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51. ScCl3
52. HCl
53. PtO2
54. Sb(ClO3)5
55. GeS2
56. ZnO
57. VSO4
58. CuCl2
59. TiO2
60. NiN
61. Ni3(PO4)2
62. CoF3
63. Au2O3
64. Zn3P2
65. Cr(NO3)6
66. NaIO2
67. NaIO3
68. NaI
69. H2SO3
70. H2CO3
71. AlN
72. AlH3
73. Li3AsO4
74. NaCN
75. Na2O2
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76. Li3PO3
77. KHCO3
78. HF
79. AuI2
80. KMnO4
81. Na2Cr2O7
82. Ag2CrO4
83. AgCl
84. NaCH3COO
85. RaF2
86. KSCN
87. FeS
88. Fe2(SO3)3
89. FeSO4
90. MgS
91. Na2S2O3
92. RbCl
93. Cu(OH)2
94. Mg3N2
95. Cu3N
96. LiH
97. K2O
98. K2O2
99. Li3N
100. DsCl3
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AP WORKSHEET 00g: Inorganic Nomenclature III (Acids)
1. Write the formula of each of the following acids. (14)
(a) Nitric acid
(b) Chloric acid
(c) Hydrochloric acid
(d) Sulfurous acid
(e) Chlorous acid
(f) Hydrobromic acid
(g) Phosphoric acid
(h) Nitrous acid
(i) Perchloric acid
(j) Hydrofluoric acid
(k) Perbromic acid
(l) Sulfuric acid
(m) Bromic acid
(n) Hypoiodous acid
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2. Name the following acids. (14)
(a) HClO3
(b) H3PO4
(c) HI
(d) H2SO3
(e) HNO3
(f) HF
(g) HC2H3O2
(h) HBr
(i) H3PO3
(j) HClO
(k) H2CO3
(l) H2SO4
(m) HBrO2
(n) HNO2
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AP WORKSHEET 00h: Inorganic Nomenclature IV Formula Name
1 HClO2
2 NaBr
3 K2CO3
4 Cu(HCO3)2
5 Al2(SO3)3
6 SrH2
7 BI3
8 N2O4
9 SeF6
10 P2O5
11 FeCl2
12 OF
13 Cu2SO4
14 ClF5
15 MgSO4
16 MnO
17 FeO
18 Mg(OH)2
19 CrO3
20 Rb2O
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HONORS WORKSHEET 4s: Stoichiometry Summary
• TYPE 1: Those involving Avogadro’s number (the mole concept). Question 1 A sample of Ge is found to contain 9.7 x 1023 atoms of Ge. How many moles of Ge atoms are in the sample? (1) Question 2 How many W atoms are found in 0.43 moles of pure W? (1)
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• TYPE 2: Those involving the relationship between mass, moles and molar mass (RAM, RFM, RMM).
Question 3 What is the mass in grams of 0.531 moles of Sn? (1) Question 4 How many moles of Ca are in 2.03 g of Ca? (1) Question 5 5.00 moles of a binary, group II oxide are found to have a mass of 521 g. Identify the group II metal. (2)
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• TYPE 3: Those combining types #1 & #2.
Question 6 How many Ta atoms are found in a 1.231 g sample of Ta? (2) Question 7 What is the mass of 8.11 x 1023 atoms of Sulfur? (2) Question 8 What mass of Cu atoms have the same number of atoms as there are in a 4.21g sample of Si? (2)
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• TYPE 4: % by Mass Composition.
Question 9 Calculate the percent by mass composition of dimethylether, CH3OCH3. (2)
Question 10 What is the percent by mass composition of aluminum sulfate? (2) Question 11 A compound that contains a complex ion has the formula Al4[Fe(CN)6]3. What is the percent by mass composition of this compound? (2) • TYPE 5: Empirical formula.
Question 12 A compound containing silver and chlorine contains 75.3% Ag. What is the empirical formula of the compound? (2)
Question 13 In a vigorous chemical reaction, 1.403 g of sodium metal is completely reacted with 1.159 g of fluorine gas. What is the empirical formula of the compound formed? (3)
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• TYPE 6: Molecular formulae from empirical formulae.
Question 14 What is the molecular formula of hydrocarbon that has an empirical formula of CH and a molecular mass of 78 gmol-1? (1) Question 15 A compound contains 48.65% carbon, 8.108% hydrogen, and the remainder oxygen. The molecular mass of this compound is approximately 74.00 g/mol. What is the empirical formula? What is the molecular formula? (3) • TYPE 7: Combustion analysis.
Question 16 The combustion of 4.000 g of a compound that contains only C, H, N and Br yields 3.826 g of CO2 and 2.087 g of H2O. Another sample of the compound with a mass of 3.111 g is found to contain 1.803 grams of Br. What is the empirical formula of the compound? (6)
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• TYPE 8: % Yield.
Question 17 Propane will combust according to the reaction below. If 11.1 g of Propane produces 23.3 g of CO2 when burned in excess oxygen, what is the % yield? (3)
C3H8 + 5O2 è 3CO2 + 4H2O
• TYPE 9: Limiting reactant.
Question 18 Consider the reaction between Iron and anhydrous Copper (II) sulfate that produces Iron (II) sulfate and Copper metal.
(a) Write an equation for the reaction. (2) (b) If 120. g of Fe are reacted with 200. g of Copper (II) sulfate, identify the limiting
reagent. Which reagent is in excess? (2)
(c) Calculate the mass of Copper formed. (2)
(d) How much of the excess reagent is left over at the end of the reaction? (2)
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• Type 10: Analysis of hydrated salts.
Question 19 Barium Chloride is found as a hydrated salt, BaCl2.xH2O. A student carefully heats 2.50 g of the salt to a constant mass of 2.13 g. Find x. (4) • TYPE 11: Moles and reacting ratios (including solutions).
Question 20 Calcium hydrogen carbonate, Ca(HCO3)2, reacts with HCl according to the equation below.
Ca(HCO3)2 + 2HCl è CaCl2 + 2CO2 + 2H2O
(a) What volume of 0.235 M HCl solution must be present to totally react with 0.140 moles of the calcium compound? (2)
(b) How many moles of water are produced when 0.491 g of the calcium compound
combines with excess HCl? (2)
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• TYPE 12: Dilution.
Question 21 Calculate the volume of 0.120 M sulfuric acid that must be diluted with water to produce 3.00 L of 0.018 M sulfuric acid. (2)
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AP WORKSHEET 00s: Preamble Summary 1. Classify the following as either chemical or physical changes. (3)
(a) Ice melting (b) Gasoline burning (c) Evaporation of perfume from an open bottle 2. Mercury is a liquid metal that has a density of 13.58 g/mL. Calculate the volume of mercury
that must be poured out in order to obtain 0.5000 g of Mercury. (2)
3. Classify the following as either quantitative or qualitative observations. (4)
(a) My eyes are brown (b) My neck size is 17 inches
(c) My average grade last year was 79%
(d) Physics is a difficult subject 4. Give an example of a natural law (other than the law of conservation of mass). (1)
5. Convert these numbers to scientific notation. (2)
(a) 35800000000000
(b) 0.00000000821
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6. Round the following numbers to four figures. (6)
(a) 2.16347 x 105
(b) 4.000574 x 106
(c) 3.682417
(d) 7.2518
(e) 375.6523
(f) 21.860051 7. Perform the following conversions. (5)
(a) 0.75 kg to milligrams
(b) 1500 millimeters to km
(c) 2390 g to kg
(d) 0.52 km to meters
(e) 65 kg to g 8. Complete the following table of temperatures, performing the appropriate conversions. (18)
Kelvin Fahrenheit Celsius
200.
23.0
0.000
180.
45.0
500.
350.
97.0
30.0
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9. An experiment is performed in which the molar mass of a gas is found to be 48.45 g mol-1
.
The published (actual) value is 52.98 g mol-1
. Calculate the percentage error. (2)
10. Distinguish carefully between precision and accuracy. (2) 11. In the table below, match the scientist with the experiment. (2)
Scientist Experiment
Crookes Oil Drop
Millikan Cathode Ray
Rutherford Gold Foil
12. Consider the following pairs; does either pair represent a pair of isotopes? Explain. (4) (a)
11Na23 and
11Na24
(b)
11Na24 and
12Mg24
13. Determine the number of protons, electrons and neutrons in each of the following
isotopes. (3)
(a) 79
Au171 (b)
79Au182
(c) 35
Br-
79
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14. In the following question give the missing formula or name. (10)
Formula Name
CaS
Pb3N2
AlP
HBrO4
(NH4)2CO3
Calcium ethanoate
Phosphorous pentachloride
Strontium bromite
Potassium hydrogen carbonate
Chloric acid