Multiple choice. Choose the one alternative that best completes the statement or
answers the question.
1) What is the molecular geometry of ClF ? 4
a) Seesaw B) tetrahedral
c) square planer D) Square pyramidal
2) Using the VSEPR model, the geometry of the electron groups around the central atom in
b) Trigonal planar
e) Trigonal bipyramidal
3) Determine the vapor pressure (in mmHg) of a substance at 29 C , whose normal boiling
point is 76 C and has a ∆H vapof 38.7 kJ/mol. You may use the Claussius-Clapeyron
Ln(P 2-ln(P 1 = -∆H vap/ R [1/T2– 1/] and note that 1 atm = 760 mmHg.
4) Which is expected to have the largest dispersion forces?
A) F 2 B) C 126 C) BeCl 2 d) C3H 8
5) Consider the phase diagram below. If the dshed line at 1atm of pressure is followed from
100 to 500 C, what phase changes will occur(in order of increasing temperature)? A) Condensation, followed by vaporization
B) Sublimation, followed by deposition
C) Melting, followed by vaporization
D) Vaporization followed by deposition
E) No phase change will occur under the conditions specified
6) How much energy must be removed from a 125 g sample of benzene (molar mass=
78.11 g/mol) at 425.0K to liquify the sample the sample and lower the temperature to
335.0k? the following physical data may be useful.
∆H vap= 33.9kJ/mol
∆H fus= 9.8kJ/mol
C liq.73 J/g C
C gas= 1.06 J/g C
C sol.51 J/g Co
Tmeling 279.0 K
a) 95.4kJ b) 67.7 kJ C) 54.3 kJ D) 74.4 kJ E) 38.9 kJ
7) Indentify the compound that does not have dipole-dipole forces as its strongest force.
a) CH C2 2
c) CH B3
d) CH O3H 3 e) HCCl
8) Place the following compounds in order of increasing strength of intermolecular forces
CO 2 F2 NH 2H 3
a) F C2 < NH2CH 2 3
b) NH CH2< C3 < F 2 2
c) F <2NH CH 2 CO3 2
d) CO < 2H CH 2 F 3 2
F) NH CH2< F3< CO2 2
9) What volume of a 0.716M kBr solution is needed to provide 30.5g of kBr?
a) 184 mL B) 42.7mL c) 21.8 mL D) 357 mL
10)A solution is prepared by dissolving 40.0g of sucrose, C H O ,12 22la11mass= 342
g/mol) in 250 g. of water at 25 C. What is the vapor pressure of the solution if the vapor
pressure of water at 25 C is 23.76 mm Hg?
a) 23.6 mm Hg b) 24.0 mm Hg C) 0.198 mm Hg d) 20.5
11)Determine the molality of an aqueous solution prepared by dissolving 0.112 moles of
LiCl in 13.7 moles of H O2
A) 0.818 m B) 0.454 m C) 0.220 m D) .153 m E) 0.122 m
12)Nickel has a face-centered cubic structure and has density of 8.90g/cm . What is its
a) 997 pm b) B) 125 pm c) 249 pm d) 353pm
13)A reaction is found to have an activation energy of 108 kJ/mol. If the rate constant for
this reaction is 4.60 x 10 s at 275 k, what is the rate constant at 366 K?
a) 0.58 s -1
b) 5.4 x10 S
c) 1.7 s -1
d) 12s -4 -1
e) 1.9 x 10 S
14)Determine the concentration of N in water2exposed to air at 25 C if the atmospheric
pressure is 1.2 atm. Assume that the mole fraction of nitrogen is 0.78 in air and the
Henry’s law constant for nitrogen in water at temperature is 6.1 x 10 M/atm. -4
a) 6.5 x 10 M
b) 1.5 x 10 M -4
c) 5.7 x 10 M
d) 1.8 x 10 M -4
e) 3.6 x 10 M
15)Given the following proposed mechanism, predict the rate law for the overall reaction.
2NO + 2l → 22O Cl 2