Chapter 13
Solutions
The curve describes the solubility properties of
A liquid
An ionic solid
A covalent solid
A gas
A gas or liquid
2.0
Solubility mM
1.
2.
3.
4.
5.
1.0
0
0
15
30
45
Temperature (°C)
60
The curve describes the solubility properties of
A liquid
An ionic solid
A covalent solid
A gas
A gas or liquid
2.0
Solubility mM
1.
2.
3.
4.
5.
1.0
0
0
15
30
45
Temperature (°C)
60
Considering the substances given below, predict
which will be soluble in water.
1.
2.
3.
4.
5.
1
2
3
2, 3
1, 2, 3
CH3CH2CH2CH2CH2CH2CH2CH2OH
1
O
NH3
H3C C CH3
2
3
Considering the substances given below, predict
which will be soluble in water.
1.
2.
3.
4.
5.
1
2
3
2, 3
1, 2, 3
CH3CH2CH2CH2CH2CH2CH2CH2OH
1
O
NH3
H3C C CH3
2
3
When concentration is expressed in units
of ________ , changing temperature will affect the
solution concentration.
1.
2.
3.
4.
5.
Molality
Molarity
ppm
Molarity and molality
Molarity, molality, and ppm
When concentration is expressed in units
of ________ , changing temperature will affect the
solution concentration.
1.
2.
3.
4.
5.
Molality
Molarity
ppm
Molarity and molality
Molarity, molality, and ppm
Predict which aqueous solution will have the
lowest freezing point.
1.
2.
3.
4.
5.
0.25 m C2H5OH
0.15 m CaCl2
0.20 m NaCl
0.15 m NH4NO3
0.15 m Na3PO4
Predict which aqueous solution will have the
lowest freezing point.
1.
2.
3.
4.
5.
0.25 m C2H5OH
0.15 m CaCl2
0.20 m NaCl
0.15 m NH4NO3
0.15 m Na3PO4
Arrange the aqueous solutions according to
increasing boiling point.
1.
2.
3.
4.
5.
AlCl3 < KNO3 < Na2SO4
Na2SO4 < AlCl3 < KNO3
Na2SO4 < KNO3 < AlCl3
KNO3 < AlCl3 < Na2SO4
KNO3 < Na2SO4 < AlCl3
0.10 m Na2SO4
0.15 m AlCl3
0.20 m KNO3
Arrange the aqueous solutions according to
increasing boiling point.
1.
2.
3.
4.
5.
AlCl3 < KNO3 < Na2SO4
Na2SO4 < AlCl3 < KNO3
Na2SO4 < KNO3 < AlCl3
KNO3 < AlCl3 < Na2SO4
KNO3 < Na2SO4 < AlCl3
0.10 m Na2SO4
0.15 m AlCl3
0.20 m KNO3
Which polyethylene solution will produce the
largest osmotic pressure?
Assume that all solutions use
the same solvent and have
the same concentration.
Which polyethylene solution will produce the
largest osmotic pressure?
Assume that all solutions use
the same solvent and have
the same concentration.
From weakest to strongest, rank the
following solutions in terms of
solvent–solute interactions: NaCl in
water, butane (C4H10) in benzene
(C6H6), water in ethanol.
1. NaCl in water < C4H10 in C6H6 < water in ethanol
2. Water in ethanol < NaCl in water < C4H10 in C6H6
3. C4H10 in C6H6 < water in ethanol < NaCl in water
Correct Answer:
1. NaCl in water < C4H10 in C6H6 < water in ethanol
2. Water in ethanol < NaCl in water < C4H10 in C6H6
3. C4H10 in C6H6 < water in ethanol < NaCl in water
Butane in benzene will have only
weak dispersion force
interactions. Water in ethanol
will exhibit much stronger
hydrogen-bonding interactions.
However, NaCl in water will show
ion–dipole interactions because
NaCl will dissolve into ions.
At a certain temperature, the Henry’s
law constant for N2 is 6.0  104 M/atm.
If N2 is present at 3.0 atm, what is the
solubility of N2?
1.
2.
3.
4.
6.0  104 M
1.8  103 M
2.0  104 M
5.0  105 M
Correct Answer:
1.
2.
3.
4.
6.0  104 M
1.8  103 M
2.0  104 M
5.0  105 M
Henry’s law,
S g  kPg
Sg = (6.0  104 M/atm)(3.0 atm)
Sg = 1.8  103 M
Determine the mass percentage of
hexane in a solution containing 11 g of
butane in 110 g of hexane.
1.
2.
3.
4.
9.0 %
10. %
90.%
91 %
Correct Answer:
1.
2.
3.
4.
9.0 %
10. %
90.%
91 %
mass of component in solution
mass % of component 
100
total mass of solution
Thus,
110 g
 100 = 91%
(110 g + 11 g)
If 3.6 mg of Na+ is detected in a 200. g
sample of water from Lake Erie, what is
its concentration in ppm?
1.
2.
3.
4.
7.2 ppm
1.8 ppm
18 ppm
72 ppm
Correct Answer:
1.
2.
3.
4.
7.2 ppm
1.8 ppm
18 ppm
72 ppm
ppm of component 
mass of component in solution
106
total mass of solution
3.6 mg 0.0036 g
6

 18 ppm
10

200. g
200. g
What is the molality of 6.4 g of methanol
(CH3OH) dissolved in 50. moles of water?
1.
2.
3.
4.
0.040 m
0.22 m
0.064 m
0.11 m
Correct Answer:
1.
2.
3.
4.
m
0.040 m
0.22 m
0.064 m
0.11 m
Molality,m 
moles solute
kg of solvent
(6.4 g methanol)/(32.0 g/mol)
(50 mol water)(18.0 g/mol)(1kg/1000g)
(0.20 mol)
m
 0.22 m
(0.90 kg)
How many moles of solute are there in
240 g of a solution that is 5.0% glucose
(C6H12O6) by mass?
1.
2.
3.
4.
5.
0.033 moles
0.067 moles
0.10 moles
0.12 moles
0.20 moles
Correct Answer:
1.
2.
3.
4.
5.
0.033 moles
0.067 moles
0.10 moles
0.12 moles
0.20 moles
5.0 % glucose means 5.0 g glucose/100 g solution
(5.0 g glucose/100 g solution)(240 g solution) = 12 g
(12 g glucose)  (1 mol glucose/180 g glucose) =
0.067 moles glucose
At a certain temperature, water has a
vapor pressure of 90.0 torr. Calculate
the vapor pressure of a water solution
containing 0.080 mole sucrose and
0.72 mole water.
1. 9.0 torr
2. 10. torr
3. 80. torr
4. 81. torr
5. 90. torr
Correct Answer:
1.
2.
3.
4.
5.
9.0 torr
10. torr
80. torr
81. torr
90. torr
Pi 
P
i
total
Pi = XiPtotal
Pi = (0.72 mol/[0.72 + 0.080 mol])(90.0 torr)
Pi = (0.90)(90.0 torr) = 81. torr
Ethanol normally boils at 78.4°C. The
boiling point elevation constant for
ethanol is 1.22°C/m. What is the boiling
point of a 1.0 m solution of CaCl2 in
ethanol?
1. 77.2°C
2. 79.6°C
3. 80.8°C
4. 82.1°C
5. 83.3°C
Correct Answer:
1.
2.
3.
4.
5.
77.2°C
79.6°C
80.8°C
82.1°C
83.3°C
T b  K b m
The increase in boiling point is determined by the
molality of total particles in the solution. Thus, a
1.0 m solution of CaCl2 contains 1.0 m Ca2+ and
2.0 m Cl for a total of 3.0 m. Thus, the boiling
point is elevated 3.7°C, so it is 78.4°C + 3.7°C =
82.1°C.
At 300 K, the osmotic pressure of a
solution is 0.246 atm. What is its
concentration of the solute?
1.
2.
3.
4.
1.0 M
0.50 M
0.25 M
0.10 M
Correct Answer:
1.
2.
3.
4.
1.0 M
0.50 M
0.25 M
0.10 M
 
( )
n
V
RT  MRT
M =  /RT
M = (0.246 atm)/[(0.0821 L-atm/mol-K)(300K)]
M = (0.246 atm)/(0.2463 L-atm/mol) = 1.0 M
Which of the following is not an
example of a colloid?
1.
2.
3.
4.
5.
Fog
Smoke
Paint
Milk
Carbonated water
Correct Answer:
1.
2.
3.
4.
5.
Fog
Smoke
Paint
Milk
Carbonated water
Carbonated water is a
solution; all the other
substances in the list
are excellent examples
of colloids.