3.
Identify
all intermolecular forces present between two molecules of the same substance
for each of the following compounds.
a. CH3CH2CH3
b. CH3CH2CH2CH2OH
c. CH3CH2NH2
d. CH3CH2OCH2CH3
e. CBr4
f.
4.
For
each compound shown in the previous question, which intermolecular force has
the greatest impact on the physical properties of the substance?
5.
List
the following compounds in order of increasing boiling point.
6.
List
the compounds shown in the previous question in order of increasing vapor
pressure at ambient (room) temperature.
7.
For
each pair of compounds, identify the one with the higher boiling point.
8.
For
each pair of compounds, identify the one that is more water soluble.
9.
Calculate
the amount of heat needed to heat 125 g of solid ethanol (C2H5OH)
from its melting point, -114.3oC, to 75oC if its boiling
point is 78.4oC. The specific
heat of liquid ethanol is 2.44 J/gK. Its heat of fusion is 4.9
kJ/mol while its heat of vaporization is 38.56 kJ/mol.
10.
Calculate
the enthalpy change that occurs when 125 g of steam at 105oC is
cooled to -11oC. The specific
heat of steam is 2.080 J/gK while the specific heat
of water is 4.18 J/gK. The specific heat of ice is 2.05 J/gK. The heat of
fusion of water is 6.01 kJ/mole while the heat of
vaporization of water is 40.79 kJ/mol.
11.
Use
the phase diagram below to answer the following questions.
a. What phase change occurs going from point
B to A?
b. What phase change occurs going from pont G to H?
c. What physical state(s) is/are present at point F?
d. What physical state(s) is/are present at point D?
e. What physical state(s) is/are present at point E?
f. Which point represents the critical point of the substance?
g. Which point represents the triple point of the substance?
12.
A
solution is prepared by dissolving 10.2 g of HCl (g)
in 100.0 g of DI water. Calculate the
concentration of HCl in the following units:
a. mass %
b. mole %
c. molality
13.
Calculate
the molarity of a solution prepared by dissolving 1.083g of calcium chloride in
enough water to give 250 mL of solution.
14.
A
0.50 kilogram waste water sample contains 0.25 mg of lead. Calculate the concentration of lead in the
sample in the following units:
a. ppm
b. ppb
15.
A
10.0 mass % solution of HCl in water has a density of
1.048 g/mL.
Calculate the molarity of the HCl in the
solution.
16.
Calculate
the molality of the solution described in the
previous question.
17.
Calculate
the volume (in mL) of a 12.0 M HCl
solution needed to prepare 250.0 mL of a 0.350 M HCl solution.
18.
Calculate
the molarity of a solution prepared by diluting 25.0 mL
of 3.00 M HCl to a total volume of 500.0 mL.
19.
Calculate
the concentration (mass %) of a solution prepared by dissolving 25.0 g of 0.90
mass % NaCl in an additional 250.0 g of DI water.
20.
Calculate
the concentration of carbon dioxide in a soft drink that has gone flat after
being opened. Assume that the partial
pressure of carbon dioxide in air is 0.0003 atm and
that the Henry’s law constant for carbon dioxide in the soft drink is 3.1 x 10-2
mol/L.atm.
21.
Calculate
the pressure of oxygen needed to generate an aqueous solution that is 3.4 x 10-2
M in oxygen at 25oC if the Henry’s law constant for O2 in
water is 1.3 x 10-3 mol/L.atm
at this temperature.
22.
Calculate
the vapor pressure of a solution prepared by dissolving 125 g of urea, (NH2)2CO,
in 420.0 g of water at 25oC.
(Hint: Use the appendix in your
text to look up the vapor pressure of water at this temperature.)
23.
Calculate
the mass of urea, (NH2)2CO, that must be added to 275 g
of water to produce a solution with a vapor pressure of 25.0 mm Hg at 30.oC.
24.
Rubbing
alcohol is an aqueous solution that contains 70.%
isopropyl alcohol (commonly called IPA, C3H8O) by
mass. The density of rubbing alcohol is
0.79 g/ml at 20oC.
a. Calculate the molarity of the isopropyl alcohol in the solution.
b. Calculate the molality of the isopropyl
alcohol in the solution.
25.
Calculate
the freezing point depression of a solution prepared by dissolving 45 g of
urea, (NH2)2CO, in 105 g of DI water. Kf can
be found in your text.
26.
What
is the melting point of the solution described in question 25?
27.
Calculate
the boiling point elevation of the solution described in question 25. Kb can be found in your text.
28.
What
is the boiling point of the solution described in question 25.
29.
When
0.250 g of an nonvolatile molecular solid was
dissolved in 40.0 g of CCl4 (Kb = 5.02oC/m),
the boiling point of the solution increased by 0.357oC. Calculate the molar mass of the solid.