Review for the Chemistry Final exam.
Your final exam in chemistry will focus on second semester material. However, you
are still expected to be able to do many things from the first semester, Do not forget how
to use the periodic table for determining charges, atomic numbers etc…. In addition, you
must know all your polyatomic ions, as well as how to name compounds and write
formulas for ionic and covalent compounds. Since we have used these ideas throughout
the entire year, you should not have to do much review in these areas.
We can order the material from the second semester into 4 broad categories
I)
Stoichiometry
II)
States of matter
III)
Atomic and Molecular Structure
IV)
IM Forces, their consequences, and the enrgetics of phase change
Listed below is a detailed outline of each of these areas to help you study. However,
even if something is not specifically listed below, it is still fair game. Your notes, old
problem sets, and tests will prove invaluable in helping to study for the exam. In terms of
the textbook, we have covered Chapters 1-15, excluding chapt 12
I)
Stoichiometry and Single Replacement
a) Percent composition (section 7-3)
b) Single Replacement
c) How to use the activity series in the prediction of single replacement reactions.
d) How to write molecular, complete ionic, and net ionic equations for single replacement
reactions.
e) The fundamental difference between double and single replacement reactions.
f) What happens when an alkali metal is placed in H2O?
g) Balancing Equations
h) What does a balanced chemical equation tell you?
i) Mole – Mole conversions
j) Mass – Mass conversions
k) Mole – molecule, and mass – molecule conversions
l) Theoretical yield, actual yield, and percent yield
m) Limiting reactant (note you will not be told if you have to determine LR, you must
determine that from the problem!)
n) Gas Law Stoichiometry (also see below)
o) Molarity and how to calculate with it.
p) Dilution
q) Empirical and Molecular Formulas
II)
States of matter
a) The gas laws
i)
Boyle
ii)
Charles
iii)
Gay-Lussac
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
m)
n)
o)
p)
iv)
Avagardro
Direct and indirect proportions
The ideal gas law, and how you can derive the other gas laws from it
The combined gas law
The importance of Charles’ law in the discovery of absolute zero
The meaning of absolute zero
The meaning of pressure (its definition of force/unit area)
Barometers
Know the postulates of Kinetic Molecular Theory, and how to use them to explain the
gas laws (e.g. how can you use KMT to explain Boyle’s law, or the other three gas
laws.)
The relationship between temperature and kinetic energy (postulate 4 of KMT)
The meaning of kinetic energy and its formula
What is STP?
Dalton’s Law of partial pressures
Problems in gas law stoichiometry (combining stoic. with the gas laws i.e. problem
set problems
Ideal vs. Real gases (when does the ideal gas law break down and why?)\
Be able to compare and contrast molecular nature of solids, liquids, and gases
III) IM Forces and the energetics of phase change
a)
b)
c)
d)
e)
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
Types of Intermolecular forces
Polar molecules
Intermolecular vs. intramolecular forces
Electronegativity
Ion-ion, dipole-dipole, and London forces
Dependence of melting point and boiling point, on IM forces
Understand how intermolecular forces affect boiling point (stronger force, higher mp
and bp)
Melting point
sublimation
Phase diagrams
Normal melting and boiling points and triple point
Solubility and “like dissolves like”
Heat capacity and the storage of energy
Joules and calories
Specific heat and q = mcΔT
Endothermic and exothermic processes
Heat and changes of state
I)
heat of fusion
II)
heat of vaporization
IV) Atomic and Molecular Structure
a) The relationship between frequency, wavelength, and the speed of a wave
b) The Planck relationship (E=hf)
c) Regions of the electromagnetic spectrum and the ability to order them (this includes
knowing the wavelength range of visible light and its ordering)
d) The importance of the photoelectric effect in the understanding of photons
e) Atomic spectra
i)
What are they
ii)
How they differ from the spectra of ordinary light
iii)
How they are explained by the Bohr model
iv)
Where the Bohr model fails
f) The quantum mechanical model
g) shells, sublevels, and orbitals
h) The Aufbau principle
i) The Pauli exclusion principle
j) Hund’s rule
k) The ability to write for any element on the periodic table through Xe
i)
Complete electron configurations
ii)
Noble gas configurations
iii)
Orbital diagrams
l) What are valence electrons?
m) What are ground states and excited states?
n) What are paired and unpaired electrons?
o) What is the relationship of electron configurations to the periodic table?
p) What are the main areas of the periodic table (refer to PS)?
q) Valence vs. core electrons
r) The ability to determine the charge of the ion formed by any representative element
on the periodic table
s) Polyatomic ions (refer to handout to determine which you need to know for this test)
t) The stock system and when it is used.
u) The determination of names and formulas for ionic compounds, both for binary
compounds, as well as those with polyatomic ions
v) Naming ionic and molecular compounds
The format of the exam will be a mixture of multiple choice and problems. I would bet
there will be 40 multiple choice and 3 - 5 problems, each taking up about one half of the
exam time period. The best way to study is to do problems, and that is what we will
work on for the next two days.
Reaction review questions:
1) Balance the following chemical equations and name each product and reactant:
a) Ca(OH)2 + HCl  CaCl2 + H2O
b) Fe2O3 + C  Fe + CO2
c) P4O10 + H2O  H3PO4
d) Al + H2SO4  Al2(SO4)3 + H2
Stoichiometry Review Problems
1) The combustion of a sample of butane, C4H10, produces 3.46 g of water, as well as
CO2
a) Write the balanced equation for the reaction
b) How many moles of water were formed? How many molecules?
c) How many moles of butane burned?
d) How many grams of butane burned?
e) How many grams and moles of oxygen gas were used up?
f) What is the mass percentage of carbon in butane?
2) Hydroquinone, used as a photographic developer, is 65.4 % C, 5.5% H, and 29.1% O,
by mass. The molar mass of hydroquinone is 110.11 g.
a) Calculate the empirical and molecular formulas of hydroquinone.
b) Write down the balanced chemical equation, with states, for the combustion of
hydroquinone.
c) Find the theoretical yield of the carbon-containing product when 25 g of
hydroquinone combusts with 1.75 moles of the other reactant.
d) If 35 g of the carbon-containing product is actually made, what is the percent
yield of the reaction?
3) Suppose a solution of lithium carbonate, Li2CO3, a drug used to treat manic
depressives, is labeled 0.150 M.
a) How many moles of Li2CO3 are present in 250 ml of this solution?
b) How many grams of Li2CO3 are in 630 ml of the solution?
c) How many milliliters of the solution would be needed to supply 0.0100 moles of
Li2CO3?
d) How many milliliters of the solution would be needed to provide 0.0800 g of
Li2CO3?
4) You can dissolve an aluminum soft drink can in an aqueous base such as potassium
hydroxide. The reaction is:
2Al(s) + 2KOH(aq) + 6H2O(l)  2KAl(OH)4(aq) + 3H2(g)
If you place 2.05 g of aluminum in a beaker with 125 ml of 1.25 M KOH and excess
water, will any aluminum remain? Explain your reasoning. What mass of KAl(OH)4 is
produced?
Gas Review Questions:
1) Carry out the following conversions:
a) 735 mm Hg to torr
b) 740 torr to atm
c) 2.3 atm to mm Hg
2) A sample of 4.18 mol of H2 at 18.0 Degrees C occupies a volume of 24.0 L.
Under what pressure, in atmospheres, is this sample?
3) A sample of helium at a pressure of 740 torr and in a volume of 2.58 L was heated
from 24.0 to 75.0 degrees C. The volume of the container expanded to 2.81 L.
What was the final pressure (in torr) of the helium?
4) Propylene, C3H6, reacts with hydrogen under pressure to give propane, C3H8:
C3H6(g) + H2(g)  C3H8_(g)
A sample of 18 g of propylene requires how many liters of hydrogen to react when
measured at 740 torr and 24 degrees C?
5) Let us say that you have 5 moles of gas in a 2 liter container at 25 degrees C. If
40% of the gas is O2 and 60% is N2.
a) How many moles of O2 do you have?
b) How many grams of N2 do you have?
c) What is the pressure of the O2 in the container? The N2?
d) What is the total pressure in the container?
6) Explain in terms of the kinetic molecular theory how heating a gas at constant
volume makes its pressure increase.
7) What postulates of the kinetic theory are not strictly true and why?
Atomic and Molecular Structure Review Questions:
(b) A certain line in the spectrum of atomic hydrogen is associated with the electronic
transition of the H atom from the sixth energy level (n = 6) to the second energy
level (n = 2).
(i) Indicate whether the H atom emits energy or whether it absorbs energy during
the transition. Justify your answer.
(ii) Calculate the wavelength, in nm, of the radiation associated with the spectral
line.
(iii) Account for the observation that the amount of energy associated with the
same electronic transition (n = 6 to n = 2) in the He+ ion is greater than that
associated with the corresponding transition in the H atom.
Solids and Liquids review questions:
1) Sketch the phase diagram for a substance that has a triple point at –15.0 degrees C
and 0.30 atm, melts at –10.0 degrees C at 1 atm, and has a normal boiling point of 90
degrees C. Label the different phases of the substance on the diagram.
Energetics of Phase Change Review Questions
1) How many joules of heat are needed to increase the temperature of 25g of water from
20 to 99 degrees C?
2) If the heat of fusion of ritaonium is 45 kJ/mol and ritaonium has a molar mass of 23
g/mol, calculate the amount of energy needed to melt 904 g of the susbtance.