1) Which of the following correctly represents the electron affinity of bromine?
A) Br (g) → Br+ (g) + e–
B) Br (g) + e– → Br– (g)
C) Br2 (g) + e– → Br– (g)
D) Br2 (g) + 2e– → 2Br– (g)
E) Br+ (g) + e– → Br (g)
2) The phase changes B –> C and D –> E are not associated with temperature increases
because the heat energy is used up to ________.
A) increase distances between molecules
B) break intramolecular bonds
C) rearrange atoms within molecules
D) increase the velocity of molecules
E) increase the density of the sample
3) In the coal-gasification process, carbon monoxide is converted to carbon dioxide via
the following reaction:
CO (g) + H2O (g) CO2 (g) + H2 (g)
In an experiment, 0.35 mol of CO and 0.40 mol of H2O were placed in a 1.00-L
reaction vessel. At equilibrium, there were 0.22 mol of CO remaining. Keq at the
temperature of the experiment is ________.
A) 5.5
B) 0.75
C) 3.5
D) 0.28
E) 1.0
4) Which component of air is the primary problem in a condition known as “the
bends”?
A) O2
B) CO2
C) He
D) N2
E) CO
5) The combustion of propane (C3H8) produces CO2 and H2O:
C3H8 (g) + 5O2 (g) → 3CO2 (g) + 4H2O (g)
The reaction of 2.5 mol of O2 will produce ________ mol of H2O.
A) 4.0
B) 3.0
C) 2.5
D) 2.0
E) 1.0
6) What is the mass % of carbon in dimethylsulfoxide (C2H6SO) rounded to three
significant figures?
A) 25.4
B) 28.6
C) 30.7
D) 7.74
E) 78.1
7) An aliquot (28.7 mL) of a KOH solution required 31.3 mL of 0.118 M HCl for
neutralization. What mass (g) of KOH was in the original sample?
A) 1.64
B) 7.28
C) 0.173
D) 0.207
E) 0.414
8) Electrons in ________ bonds remain localized between two atoms. Electrons in
________ bonds can become delocalized between more than two atoms.
A) pi, sigma
B) sigma, pi
C) pi, pi
D) sigma, sigma
E) ionic, sigma
9) When the following equation is balanced, the coefficients are ________.
C8H18 + O2 → CO2 + H2O
A) 4, 50, 16, 18
B) 1, 5, 2, 2
C) 2, 2, 7, 1
D) 1, 13, 8, 9
E) 2, 25, 16, 18
10) Between which two elements is the difference in metallic character the greatest?
A) Rb and O
B) O and I
C) Rb and I
D) Li and O
E) Li and Rb
11) The molarity of an aqueous solution containing 75.3 g of glucose (C6H12O6) in 35.5
mL of solution is ________.
A) 1.85
B) 2.12
C) 0.197
D) 3.52
E) 11.8
12) Which one of the following concentration units varies with temperature?
A) molarity
B) mass percent
C) mole fraction
D) molality
E) all of the above
13) The addition of sodium hydroxide and ________ to water produces a buffer
solution.
A) HCl
B) NaC2H3O2
C) NaF
D) NH3
E) none of the above
14) A 0.100 M solution of ________ will contain the highest concentration of
potassium ions.
A) potassium phosphate
B) potassium hydrogen carbonate
C) potassium hypochlorite
D) potassium iodide
E) potassium oxide
15) Boron triiodide (BI3) melts at 49.9 oC and boils at 209.5 oC at a constant pressure
of 1 atm. What state of matter must a sample of boron triiodide be in at 100oC and 1
atm?
A) liquid
B) gas
C) solid
D) solid and liquid in equilibrium
E) liquid and gas in equilibrium
16) The temperature of a 15-g sample of lead metal increases from 22 °C to 37 °C upon
the addition of 29.0 J of heat. The specific heat capacity of the lead is ________ J/g-K.
A) 7.8
B) 1.9
C) 29
D) 0.13
E) -29
17) The value of G o at 25 oC for the following reaction:
C2H4 (g) + H2 (g) –> C2H6 (g)
is ________ kJ/mol. At 298 K, H o for this reaction is -137.5 kJ/mol, and S o is +120.5
J/K.
A) -35800
B) -173.4
C) 35800
D) -101.7
E) -274.2
18) Consider the following reaction at equilibrium:
2CO2 (g) 2CO (g) + O2 (g)Ho = -514 kJ
Le Ch¢telier’s principle predicts that removing O2 (g) to the reaction container will
________.
A) increase the partial pressure of CO
B) decrease the partial pressure of CO
C) increase the partial pressure of CO2
D) increase the value of the equilibrium constant
E) decrease the value of the equilibrium constant