Chapter 11 – Intermolecular Forces and Liquids and Solids
80.
Which of the following constants is/are needed to calculate the amount of energy required to heat 12.0g of H2O(l) at 30.0C
to H2O(l) at 85.0C?
I. Hfus (H2O)
II. Hvap (H2O)
III. specific heat of H2O(s)
IV. specific heat of H2O(l)
V. specific heat of H2O(g)
81. The vapor pressure of a liquid in a closed container depends upon
Chapter 11 – Intermolecular Forces and Liquids and Solids
82. The vapor pressure of ethanol is 400 mmHg at 63.5C. Its molar heat of vaporization is
39.3 kJ/mol. What is the vapor pressure of ethanol, in mmHg, at 34.9C?
83. Solid iodine has a vapor pressure of 1.0 mmHg at 39C. How many moles of iodine will
sublime into a 500 mL flask at this temperature? If the volume of the flask is doubled at
constant temperature, what will happen to the equilibrium vapor pressure of I2? (Assume
some solid I2 is always present in the container.)
Chapter 11 – Intermolecular Forces and Liquids and Solids
84. 3.59 g of water was introduced into an evacuated 1.50 L flask at 30C. What mass of
water will evaporate? (Vapor pressure of water at 30C is 31.82 mmHg.)
85. The molar heats of sublimation and fusion of iodine are 62.3 kJ/mol and15.3 kJ/mol,
respectively. Calculate the molar heat of vaporization of liquid iodine.
Chapter 11 – Intermolecular Forces and Liquids and Solids
86.
Octane is a liquid component of gasoline. Given the following vapor pressures of octane at various temperatures, estimate the
boiling point of octane in Leadville, Colorado, where the atmospheric pressure is 496 mmHg.
400 mmHg @ 104C, 500 mmHg @ 111C, 600 mmHg @ 117C, 700 mmHg @ 122C, 760 mmHg @ 125C
87.
Use the following data to determine the molar heat of vaporization of chlorine.
T (C)
–84.5
–71.2
–47.3
P (mmHg)
40.0
100.0
400.0
Chapter 11 – Intermolecular Forces and Liquids and Solids
88. The molar enthalpy of vaporization of hexane (C6H14) is 28.9 kJ/mol, and its normal
boiling point is 68.73C. What is the vapor pressure of hexane at 25C?
89. The molar enthalpy of vaporization of boron tribromide is 30.5 kJ/mol, and its normal
boiling point is 91C. What is the vapor pressure of BBr3 at 20C?
Chapter 11 – Intermolecular Forces and Liquids and Solids
90. The molar enthalpy of vaporization of carbon disulfide is 26.74 kJ/mol, and its normal
boiling point is 46C. What is the vapor pressure of CS2 at 0C?
91. The normal boiling point of methanol (CH3OH) is 64.6C. Given that the vapor pressure
of methanol is 75.0 torr at 15.2C, calculate the molar enthalpy of vaporization of methanol.
Chapter 11 – Intermolecular Forces and Liquids and Solids
92. The normal boiling point of bromine is 58.8C. Given that the vapor pressure of bromine
is 75.0 torr at 2.5C, calculate the molar enthalpy of vaporization of bromine.
93. Find the temperature at which water boils on a day in the mountains when the barometric
pressure is 593 mmHg. (Given: the heat of vaporization of water is 40.79 kJ/mol)
Chapter 11 – Intermolecular Forces and Liquids and Solids
94. Find the temperature at which ethanol boils on a day in the mountains when the
barometric pressure is 547 mmHg. (Given: The heat of vaporization of ethanol is 39.3 kJ/mol;
the normal boiling point of ethanol is 78.3C.)
Chapter 11 – Intermolecular Forces and Liquids and Solids
95.
Based on the phase diagram shown below, how will the melting point of the substance change if the pressure is increased
above 1 atm?
Chapter 11 – Intermolecular Forces and Liquids and Solids
96. Of the following, which is the dominant (strongest) type of intermolecular force present in
RbCl(s)?
97. Identify the dominant (strongest) type of intermolecular force present in H2S(g).
98. Identify the dominant (strongest) type of intermolecular force present in NH3(l).
Chapter 11 – Intermolecular Forces and Liquids and Solids
99. Identify the dominant (strongest) type of intermolecular force present in Cl2(l).
100. Indicate all the types of intermolecular forces of attraction in F2(l).
101. Indicate all the types of intermolecular forces of attraction in HF(l).
Chapter 11 – Intermolecular Forces and Liquids and Solids
102. Indicate all the types of intermolecular forces of attraction in SO2(l).
103. Indicate all the types of intermolecular forces of attraction in He(l).
104. Indicate all the types of intermolecular forces of attraction in C2H6(g).
Chapter 11 – Intermolecular Forces and Liquids and Solids
105. Indicate all the types of intermolecular forces of attraction in CHCl3(l).
106. Indicate all the types of intermolecular forces of attraction in SF4(g).
107. Indicate all the types of intermolecular forces of attraction in CF4(g).
Chapter 11 – Intermolecular Forces and Liquids and Solids
108. Indicate all the types of intermolecular forces of attraction in HCl(g).
109. Indicate all the types of intermolecular forces of attraction in CH3OH(l).
110. Select True or False: H2S has stronger intermolecular forces of attraction than H2Se.
Chapter 11 – Intermolecular Forces and Liquids and Solids
112. Select True or False: CH4 has a higher boiling point than CH3OH.
113. Which type of intermolecular force is the strongest? (ionic, ion-dipole, dipole-dipole,
hydrogen bonding, dispersion)
Chapter 11 – Intermolecular Forces and Liquids and Solids
115. Select True or False: The meniscus for water is curved upward at the edges (i.e., it is
Chapter 11 – Intermolecular Forces and Liquids and Solids
116. Iron crystallizes in a body-centered cubic unit. The edge of this cell is 287 pm. What is
the density of iron?
Chapter 11 – Intermolecular Forces and Liquids and Solids
117. Copper crystallizes in a face-centered cubic unit cell. The density of copper is 8.94
g/cm3. Calculate the length of the edge of the unit cell in pm.
119. Select True or False: At room temperature, honey is more viscous than mustard.
Chapter 11 – Intermolecular Forces and Liquids and Solids
120.
Select True or False: The molar heat of vaporization (Hvap) of H2Se is greater than H2O.
122. Select True or False: NH3 has a higher boiling point than CH4.