Update 2026 | 100% Correct Answers | Exam Prep
1. Describe why vaporization is considered an endothermic process.
Vaporization is considered an endothermic process because it
requires the absorption of heat to convert liquid into gas.
Vaporization occurs without any heat exchange.
Vaporization is endothermic because it cools the surrounding
environment.
Vaporization is exothermic because it releases heat when a liquid turns
into gas.
2. Describe the effect of adding a strong base like NaOH to a strong acid like
HNO3 during a titration.
Adding NaOH neutralizes HNO3, decreasing the concentration of
H+ ions and increasing the pH.
Adding NaOH only affects the temperature of the solution.
Adding NaOH increases the concentration of H+ ions, lowering the
pH.
Adding NaOH has no effect on the pH of the solution.
3. Given the concentrations of Li, H2O, LiOH, and H2 in a 1 L flask, how would
you calculate the reaction quotient for the reaction 2 Li(s) + 2 H2O(l) ⇌ 2
LiOH(aq) + H2(g)?
Q = [H2]^2 / ([LiOH] * [H2O])
Q = [LiOH] * [H2] / ([Li]^2 * [H2O]^2)
Q = [LiOH]^2 * [H2] / ([Li]^2 * [H2O]^2)
, Q = [Li]^2 * [H2O]^2 / ([LiOH]^2 * [H2])
4. According to saturation curves shown in the figure, which of the following
solutions is supersaturated?
80g of NaCH3COO in 100g of water at 40ºC
80g of NaCH3COO in 200g of water at 40ºC
140g of NaCH3COO in 100g of water at 80ºC
40g of NaCH3COO in 100g of water at 40ºC
5. If you have 11.0 g of liquid ethanol, what would be the ΔH for the phase
change to solid ethanol using the given ΔHfrz?
-9.8 kJ
-5.5 kJ
-10.0 kJ
-12.0 kJ
6. Consider the dimerization of nitrogen dioxide at room temperature: 2NO2 (g)
<-> N2O4 (g) Keq= 8 atm^-1. If the equilibrium partial pressure of nitrogen
, dioxide in a container is 0.5 atm, what is the partial pressure of dinitrogen
tetroxide?
0.5 atm
2 atm
0.03 atm
4 atm
7. Describe how to calculate the hydroxide ion concentration from the given
hydronium ion concentration in a solution.
Hydroxide ion concentration can be calculated by subtracting
hydronium concentration from 1.
Hydroxide ion concentration is equal to the molarity of the acid.
The hydroxide ion concentration is found by multiplying the
hydronium ion concentration by 2.
To find the hydroxide ion concentration, use the formula [OH-] = Kw
/ [H3O+], where Kw is 1.0 x 10^-14.
8. Consider the following equilibrium system: CO2(g) + H2(g) <=> CO(g) +
H2O(g). Which of the following, when added to the system above, would
result in a decrease in [H2O(g)] relative to the previous equilibrium?
CO(g)
H2(g)
H2O(g)
CO2(g)
9. A transition state
, is a state that is always in transition
is the highest energy point between reactant and product
is the lowest energy point between reactant and product
increases the rate of reaction by providing an alternate mechanism
10. If 50 g of sugar were added to 100 g of water at 20 oC to form a solution,
how would you describe the solution?
Saturated
Super saturated
Unsaturated
Not enough information
11. What is the rate constant for the thermal decomposition of chloroethane at
500 °C?
1.0 x 10-3 s-1
2.0 x 10-3 s-1
1.3 x 10-3 s-1
1.5 x 10-3 s-1
12. What is the formula used to calculate the rate constant in relation to
activation energy and frequency factor?
k = A * e^(-Ea/RT)
k = A * RT
k = A + Ea
k = Ea / RT