Question 1

A liquid may be made to boil at room temperature, simply be lowering the pressure.

Accepted Answer

A) True 
 B)False

Question 2

In cubic closest packing, the unit cell is body-centered cubic.

Accepted Answer

A) True 
 B)False

Question 3

Of the five major types of crystalline solid, which would you expect each of the following to form? (e.g., H2O: molecular)
A) Sn
B) Si
C) KCl
D) Xe
E) F2

Accepted Answer

A) metallic 
B) netw

Question 4

The phase diagram of a substance shows the energy changes associated with changes of state.

Accepted Answer

A) True 
 B)False

Question 5

Only molecules which do not have dipole moments can experience dispersion forces.

Accepted Answer

A) True 
 B)False

Question 6

The meniscus of mercury in a glass capillary tube is convex because of

Accepted Answer

A)  the very high density of mercury as compared with water. 
B)  the low surface tension of mercury. 
C)  the greater attraction of mercury atoms to the glass than to each other. 
D)  the weaker attraction of mercury atoms to the glass than to each other. 
E)  electrostatic repulsion between the glass and the mercury. 
A)  the very high density of mercury as compared with water. 
B)  the low surface tension of mercury. 
C)  the greater attraction of mercury atoms to the glass than to each other. 
D)  the weaker attraction of mercury atoms to the glass than to each other. 
E)  electrostatic repulsion between the glass and the mercury.

Question 7

Which of the following pairs of substances is arranged so that the one with higher viscosity is listed first?

Accepted Answer

A)    
B)    
C)    
D)    
E)  None of these choices is correct. 
A)    
B)    
C)    
D)    
E)  None of these choices is correct.

Question 8

Which of the following pairs is arranged with the particle of higher polarizability listed first?

Accepted Answer

A)  Se2-, S2- 
B)  I, I- 
C)  Mg2+, Mg 
D)  Br, I 
E)  None of these choices is correct. 
A)  Se2-, S2- 
B)  I, I- 
C)  Mg2+, Mg 
D)  Br, I 
E)  None of these choices is correct.

Question 9

When liquid bromine is cooled to form a solid, which of the following types of solid would it form?

Accepted Answer

A)  atomic 
B)  metallic 
C)  molecular 
D)  ionic 
E)  covalent network 
A)  atomic 
B)  metallic 
C)  molecular 
D)  ionic 
E)  covalent network

Question 10

The normal boiling point of ether is 307.8 K. Calculate the temperature at which its vapor pressure is exactly half of that at its normal boiling point. The heat of vaporization for ether is 26.69 kJ/mol.

Accepted Answer

A)  305 K 
B)  302 K 
C)  295 K 
D)  289 K 
E)  281 K 
A)  305 K 
B)  302 K 
C)  295 K 
D)  289 K 
E)  281 K

Question 11

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.

Question 12

All gases can be liquefied at room temperature simply by increasing the pressure on the gas.

Accepted Answer

A) True 
 B)False

Question 13

A metal with a body-centered cubic lattice will have ______ atom(s) per unit cell.

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  9 
A)  1 
B)  2 
C)  3 
D)  4 
E)  9

Question 14

A temperature increase causes __________________ in the conductivity of a conductor.

Accepted Answer

A)  a decrease 
B)  an increase 
C)  an increase or decrease (depending on the conductor) 
D)  a modulation 
E)  no change 
A)  a decrease 
B)  an increase 
C)  an increase or decrease (depending on the conductor) 
D)  a modulation 
E)  no change

Question 15

Which one of the following statements about unit cells and packing in solids is incorrect?

Accepted Answer

A)  In any unit cell of a solid crystal, each face of the cell must have an opposite face which is equal and parallel to it. 
B)  The faces of a unit cell must all be at angles of 90$\degree$to each other. 
C)  The coordination number of atoms in a close packed metal is 12. 
D)  The packing efficiency in fcc structures is higher than in bcc structures. 
E)  The packing efficiency in fcc and hcp structures is the same. 
A)  In any unit cell of a solid crystal, each face of the cell must have an opposite face which is equal and parallel to it. 
B)  The faces of a unit cell must all be at angles of 90$\degree$to each other. 
C)  The coordination number of atoms in a close packed metal is 12. 
D)  The packing efficiency in fcc structures is higher than in bcc structures. 
E)  The packing efficiency in fcc and hcp structures is the same.

Question 16

A sample of octane in equilibrium with its vapor in a closed 1.0-L container has a vapor pressure of 50.0 torr at 45$\degree$C. The container's volume is increased to 2.0 L at constant temperature and the liquid/vapor equilibrium is reestablished. What is the vapor pressure?

Accepted Answer

A)  > 50.0 torr 
B)  50.0 torr 
C)  25.0 torr 
D)  The mass of the octane vapor is needed to calculate the vapor pressure. 
E)  The external pressure is needed to calculate the vapor pressure. 
A)  > 50.0 torr 
B)  50.0 torr 
C)  25.0 torr 
D)  The mass of the octane vapor is needed to calculate the vapor pressure. 
E)  The external pressure is needed to calculate the vapor pressure.

Question 17

A temperature increase causes __________________ in the conductivity of a semiconductor.

Accepted Answer

A)  a decrease 
B)  an increase 
C)  a modulation 
D)  an increase or decrease (depending on the semiconductor) 
E)  no change 
A)  a decrease 
B)  an increase 
C)  a modulation 
D)  an increase or decrease (depending on the semiconductor) 
E)  no change

Exam 12: Intermolecular Forces: Liquids, Solids, and Phase Changes

A liquid may be made to boil at room temperature, simply be lowering the pressure.

In cubic closest packing, the unit cell is body-centered cubic.

Of the five major types of crystalline solid, which would you expect each of the following to form? (e.g., H2O: molecular) A) Sn B) Si C) KCl D) Xe E) F2

The phase diagram of a substance shows the energy changes associated with changes of state.

Only molecules which do not have dipole moments can experience dispersion forces.

The meniscus of mercury in a glass capillary tube is convex because of

Which of the following pairs of substances is arranged so that the one with higher viscosity is listed first?

Which of the following pairs is arranged with the particle of higher polarizability listed first?

When liquid bromine is cooled to form a solid, which of the following types of solid would it form?

The normal boiling point of ether is 307.8 K. Calculate the temperature at which its vapor pressure is exactly half of that at its normal boiling point. The heat of vaporization for ether is 26.69 kJ/mol.

Ammonia's unusually high melting point is the result of

All gases can be liquefied at room temperature simply by increasing the pressure on the gas.

A metal with a body-centered cubic lattice will have ______ atom(s) per unit cell.

A temperature increase causes __________________ in the conductivity of a conductor.

Which one of the following statements about unit cells and packing in solids is incorrect?

A sample of octane in equilibrium with its vapor in a closed 1.0-L container has a vapor pressure of 50.0 torr at 45 °\degree° C. The container's volume is increased to 2.0 L at constant temperature and the liquid/vapor equilibrium is reestablished. What is the vapor pressure?

A temperature increase causes __________________ in the conductivity of a semiconductor.

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Of the five major types of crystalline solid, which would you expect each of the following to form? (e.g., H₂O: molecular) A) Sn B) Si C) KCl D) Xe E) F₂

A sample of octane in equilibrium with its vapor in a closed 1.0-L container has a vapor pressure of 50.0 torr at 45 $\degree$ C. The container's volume is increased to 2.0 L at constant temperature and the liquid/vapor equilibrium is reestablished. What is the vapor pressure?