Question 1

Helium atoms do not combine to form He2 molecules, yet He atoms do attract one another weakly through

Accepted Answer

A)  dipole-dipole forces. 
B)  ion-dipole forces. 
C)  dispersion forces. 
D)  dipole-induced dipole forces. 
E)  hydrogen bonding. 
A)  dipole-dipole forces. 
B)  ion-dipole forces. 
C)  dispersion forces. 
D)  dipole-induced dipole forces. 
E)  hydrogen bonding.

Question 2

________ ________ is another name given for dispersion forces.

Accepted Answer

The answer of ________ ________ is another name given for...

Question 3

For the solid forms of the following elements, which one is most likely to be of the molecular type?

Accepted Answer

A)  Cs 
B)  C 
C)  Pb 
D)  S 
E)  Cr 
A)  Cs 
B)  C 
C)  Pb 
D)  S 
E)  Cr

Question 4

The molar enthalpy of vaporization of hexane (C6H14) is 28.9 kJ/mol, and its normal boiling point is 68.73°C. What is the vapor pressure of hexane at 25°C? (R = 8.314 J/K • mol)

Accepted Answer

A)  171 torr 
B)  4.44 torr 
C)  117 torr 
D)  3370 torr 
E)  759 torr 
A)  171 torr 
B)  4.44 torr 
C)  117 torr 
D)  3370 torr 
E)  759 torr

Question 5

Which of the following statements is true?

Accepted Answer

A)  The higher the viscosity, the faster a liquid flows. 
B)  The viscosity increases with increasing temperature. 
C)  The stronger the intermolecular forces, the higher the viscosity. 
D)  Hydrogen bonding in water gives rise to its unusually low viscosity. 
E)  The viscosity of gases is larger than the viscosity of liquids. 
A)  The higher the viscosity, the faster a liquid flows. 
B)  The viscosity increases with increasing temperature. 
C)  The stronger the intermolecular forces, the higher the viscosity. 
D)  Hydrogen bonding in water gives rise to its unusually low viscosity. 
E)  The viscosity of gases is larger than the viscosity of liquids.

Question 6

Identify the dominant (strongest) type of intermolecular force present in H2S(g).

Accepted Answer

Question 7

What quantity of heat is required to melt 2.00 kg of iron at its melting point (1809 K)? For iron, ΔHfus = 13.80 kJ/mol.

Accepted Answer

A)  0.385 kJ 
B)  6.90 kJ 
C)  27.6 kJ 
D)  494 kJ 
E)  771 kJ 
A)  0.385 kJ 
B)  6.90 kJ 
C)  27.6 kJ 
D)  494 kJ 
E)  771 kJ

Question 8

Ethanol (C2H5-OH) will have a greater viscosity than ethylene glycol (HO-CH2CH2-OH) at the same temperature.

Accepted Answer

A) True 
 B)False

Question 9

Diethyl ether, (CH3CH2)2O, used as a solvent for extraction of organic compounds from aqueous solutions, has a high vapor pressure, which makes it a potential fire hazard in laboratories in which it is used. How much energy is released when 100.0 g is cooled from 53.0°C to 10.0°C?

Accepted Answer

A)  10.1 kJ 
B)  16.1 kJ 
C)  21.6 kJ 
D)  35.1 kJ 
E)  48.6 kJ 
A)  10.1 kJ 
B)  16.1 kJ 
C)  21.6 kJ 
D)  35.1 kJ 
E)  48.6 kJ

Question 10

________ ________ are solids that lack a regular three-dimensional arrangement of atoms.

Accepted Answer

The answer of ________ ________ are solids that lack a...

Question 11

Which statement concerning the vapor pressures of water and methanol (CH3OH) is true?

Accepted Answer

A)  At 25ºC, methanol has a higher vapor pressure than water because methanol has a lower normal boiling point than water. 
B)  At 25ºC, methanol has a higher vapor pressure than water because methanol is a poorer solvent than water. 
C)  At 25ºC, methanol has a higher vapor pressure than water because methanol is a less viscous liquid than water. 
D)  At 25ºC, methanol has a higher vapor pressure than water because the density of methanol is less than the density of water. 
E)  At 25ºC, methanol has a higher vapor pressure than water because methanol has weaker intermolecular forces than water. 
A)  At 25ºC, methanol has a higher vapor pressure than water because methanol has a lower normal boiling point than water. 
B)  At 25ºC, methanol has a higher vapor pressure than water because methanol is a poorer solvent than water. 
C)  At 25ºC, methanol has a higher vapor pressure than water because methanol is a less viscous liquid than water. 
D)  At 25ºC, methanol has a higher vapor pressure than water because the density of methanol is less than the density of water. 
E)  At 25ºC, methanol has a higher vapor pressure than water because methanol has weaker intermolecular forces than water.

Question 12

The maximum number of phases of a single substance which can coexist in equilibrium is two.

Accepted Answer

A) True 
 B)False

Question 13

________ is the name given to the phase change from a gas directly to a liquid.

Accepted Answer

The answer of ________ is the name given to the...

Question 14

Which would be expected to have the highest surface tension at a given temperature?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 15

A liquid boils when its

Accepted Answer

A)  vapor pressure is exactly 1 atmosphere. 
B)  vapor pressure is equal to or greater than the external pressure. 
C)  temperature is equal to 273 K (standard temperature). 
D)  temperature is greater than room temperature. 
E)  thermal energy is equal to the heat of vaporization. 
A)  vapor pressure is exactly 1 atmosphere. 
B)  vapor pressure is equal to or greater than the external pressure. 
C)  temperature is equal to 273 K (standard temperature). 
D)  temperature is greater than room temperature. 
E)  thermal energy is equal to the heat of vaporization.

Question 16

Which of the following pure substances would be expected to have the highest boiling point?

Accepted Answer

A)  CF4 
B)  CCl4 
C)  CBr4 
D)  CI4 
E)  CH4 
A)  CF4 
B)  CCl4 
C)  CBr4 
D)  CI4 
E)  CH4

Question 17

Ammonia's unusually high melting point is the result of

Accepted Answer

A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  covalent bonding. 
E)  ionic bonding. 
A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  covalent bonding. 
E)  ionic bonding.

Exam 11: Intermolecular Forces and the Physical Properties of Liquids and Solids

Helium atoms do not combine to form He2 molecules, yet He atoms do attract one another weakly through

________ ________ is another name given for dispersion forces.

For the solid forms of the following elements, which one is most likely to be of the molecular type?

The molar enthalpy of vaporization of hexane (C6H14) is 28.9 kJ/mol, and its normal boiling point is 68.73°C. What is the vapor pressure of hexane at 25°C? (R = 8.314 J/K • mol)

Which of the following statements is true?

Identify the dominant (strongest) type of intermolecular force present in H2S(g).

What quantity of heat is required to melt 2.00 kg of iron at its melting point (1809 K)? For iron, ΔHfus = 13.80 kJ/mol.

Ethanol (C2H5-OH) will have a greater viscosity than ethylene glycol (HO-CH2CH2-OH) at the same temperature.

Diethyl ether, (CH3CH2)2O, used as a solvent for extraction of organic compounds from aqueous solutions, has a high vapor pressure, which makes it a potential fire hazard in laboratories in which it is used. How much energy is released when 100.0 g is cooled from 53.0°C to 10.0°C?

________ ________ are solids that lack a regular three-dimensional arrangement of atoms.

Which statement concerning the vapor pressures of water and methanol (CH3OH) is true?

The maximum number of phases of a single substance which can coexist in equilibrium is two.

________ is the name given to the phase change from a gas directly to a liquid.

Which would be expected to have the highest surface tension at a given temperature?

A liquid boils when its

Which of the following pure substances would be expected to have the highest boiling point?

Ammonia's unusually high melting point is the result of

Chemistry: the Central Science

Atoms, Molecules, and Ions

Stoichiometry: Ratios of Combination

Reactions in Aqueous Solutions

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Electron Configuration and the Periodic Table

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Molecular Geometry and Bonding Theories

Gases

Modern Materials

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy, Free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Environmental Chemistry

Coordination Chemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Organic Chemistry

Filters

Helium atoms do not combine to form He₂ molecules, yet He atoms do attract one another weakly through

is another name given for dispersion forces.

The molar enthalpy of vaporization of hexane (C₆H₁₄) is 28.9 kJ/mol, and its normal boiling point is 68.73°C. What is the vapor pressure of hexane at 25°C? (R = 8.314 J/K • mol)

Identify the dominant (strongest) type of intermolecular force present in H₂S(g).

What quantity of heat is required to melt 2.00 kg of iron at its melting point (1809 K)? For iron, ΔH_fus = 13.80 kJ/mol.

Ethanol (C₂H₅-OH) will have a greater viscosity than ethylene glycol (HO-CH₂CH₂-OH) at the same temperature.

Diethyl ether, (CH₃CH₂)₂O, used as a solvent for extraction of organic compounds from aqueous solutions, has a high vapor pressure, which makes it a potential fire hazard in laboratories in which it is used. How much energy is released when 100.0 g is cooled from 53.0°C to 10.0°C?

are solids that lack a regular three-dimensional arrangement of atoms.

Which statement concerning the vapor pressures of water and methanol (CH₃OH) is true?