1. For each of the following three reactions, in part (i) write a BALANCED equation and in part (ii) answer the question about the reaction. In part (i), coefficients should be in
terms of lowest whole numbers. Assume that solutions are aqueous unless otherwise
indicated. Represent substances in solutions as ions if the substances are extensively ionized.
Omit formulas for any ions or molecules that are unchanged by the reaction.
a. A solution of sodium sulfide is added to a solution of zinc nitrate.
i)
ii) What are the spectator ions in this reaction?
b. Magnesium turnings are added to a solution of iron(III) chloride.
i)
ii) What will be observed if a magnet is brought near the reaction vessel?
c. Lithium metal is burned in air.
i)
ii) What is the change in oxidation number for lithium?
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AP Chem 2020 Fall Final
2. A sample of dolomitic limestone containing only CaCO3 and MgCO3 was analyzed.
a. When a 0.2800 gram sample of this limestone was decomposed by heating, 75.0
milliliters of CO2 at 750 mm Hg, and 20°C were evolved. How many grams of CO2
were produced?
b. Write equations for the decomposition of both carbonates described above.
c. It was also determined that the initial sample contained 0.0448 gram of calcium. What
percent of the limestone by mass was CaCO3?
d. How many grams of the magnesium-containing product were present in the sample in
after it had been heated?
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AP Chem 2020 Fall Final
3. Use principles of atomic theory, along with the photoelectron spectroscopy data shown
below, to answer the following questions about atoms of nitrogen and calcium.
a. Examine the photoelectron spectrum for atoms of nitrogen.
i) Circle the peak that contains the first electron that would be removed from a nitrogen
atom.
ii) How much energy is required to remove this first electron?
b. Once the first electron is removed from an atom of nitrogen would you expect the energy
required to remove the second electron to be greater than, less than, or equal to the
energy required to remove the first electron? Justify your answer.
c. Explain why atoms of phosphorus have a lower first ionization energy than those of
nitrogen. Be sure to reference Coulomb’s Law in your explanation.
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AP Chem 2020 Fall Final
4. A student is asked to determine the molar enthalpy of neutralization, ΔHneut, for the
reaction represented above. The student combines equal volumes of 1.0 M HCl and 1.0 M
NaOH in an open polystyrene cup calorimeter. The heat released by the reaction is
determined by using the equation q = mcΔT.
Assume the following.
• Both solutions are at the same temperature before they are combined.
• The densities of all the solutions are the same as that of water.
• Any heat lost to the calorimeter or to the air is negligible.
• The specific heat capacity of the combined solutions is the same as that of water.
a. Give appropriate units for each of the terms in the equation q = mcΔT.
b. List the measurements that must be made in order to obtain the value of q.
c. Explain how to calculate each of the following.
i) The number of moles of water formed during the experiment
ii) The value of the molar enthalpy of neutralization, ΔHneut, for the reaction between
HCl(aq) and NaOH(aq)
d. The student repeats the experiment with the same equal volumes as before, but this time
uses 2.0 M HCl and 2.0 M NaOH.
i) Indicate whether the value of q increases, decreases, or stays the same when compared
to the first experiment. Justify your prediction.
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AP Chem 2020 Fall Final
ii) Indicate whether the value of the molar enthalpy of neutralization, ΔHneut, increases,
decreases, or stays the same when compared to the first experiment. Justify your
prediction.

e. Suppose that a significant amount of heat were lost to the air during the experiment. What
effect would this have on the calculated value of the molar enthalpy of neutralization,
ΔHneut? Justify your answer.
Conti