Question 1

Which of the following properties measures the energy needed to increase the surface area of a liquid?

Accepted Answer

A)  capillary action 
B)  surface tension 
C)  viscosity 
D)  cohesion 
E)  specific elasticity 
A)  capillary action 
B)  surface tension 
C)  viscosity 
D)  cohesion 
E)  specific elasticity

Question 2

How do the electrical properties of semiconductors differ from those of metals?

Accepted Answer

Metals are good conductors who

Question 3

Polonium crystallizes in the simple cubic lattice. What is the coordination number for Po?

Accepted Answer

A)  3 
B)  4 
C)  6 
D)  8 
E)  12 
A)  3 
B)  4 
C)  6 
D)  8 
E)  12

Question 4

Select the pair of substances in which the one with the lower vapor pressure at a given temperature is listed first.

Accepted Answer

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

Question 5

Which of the following liquid substances would you expect to have the lowest surface tension?

Accepted Answer

A)  Pb 
B)  CH3OCH3 
C)  HOCH2CH2OH 
D)  H2O 
E)  CH3CH2OH 
A)  Pb 
B)  CH3OCH3 
C)  HOCH2CH2OH 
D)  H2O 
E)  CH3CH2OH

Question 6

Which of the following atoms should have the greatest polarizability?

Accepted Answer

A)  F 
B)  Br 
C)  Po 
D)  Pb 
E)  He 
A)  F 
B)  Br 
C)  Po 
D)  Pb 
E)  He

Question 7

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

Accepted Answer

A) True 
 B)False

Question 8

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

Question 9

Octane has a vapor pressure of 40. torr at 45.1°C and 400. torr at 104.0°C. What is its heat of vaporization?

Accepted Answer

A)  39.0 kJ/mol 
B)  46.0 kJ/mol 
C)  590 kJ/mol 
D)  710 kJ/mol 
E)  none of the above 
A)  39.0 kJ/mol 
B)  46.0 kJ/mol 
C)  590 kJ/mol 
D)  710 kJ/mol 
E)  none of the above

Question 10

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

Accepted Answer

A) True 
 B)False

Question 11

Draw a fully labeled phase diagram (P versus T) of a substance whose solid phase can melt due to applied pressure (i.e., solid is less dense than liquid). Clearly label the triple point and the critical temperature on your diagram.

Accepted Answer

The answer of Draw a fully labeled phase diagram (P...

Question 12

Consider the following phase diagram and identify the process occurring as one goes from point C to point D.

Accepted Answer

A)  increasing temperature with a phase change from solid to liquid 
B)  increasing temperature with a phase change from solid to vapor 
C)  increasing temperature with a phase change from liquid to vapor 
D)  increasing temperature with no phase change 
E)  increasing temperature beyond the critical point 
A)  increasing temperature with a phase change from solid to liquid 
B)  increasing temperature with a phase change from solid to vapor 
C)  increasing temperature with a phase change from liquid to vapor 
D)  increasing temperature with no phase change 
E)  increasing temperature beyond the critical point

Question 13

Iron has a body-centered cubic unit cell, and a density of 7.87 g/cm3. Calculate the edge length of the unit cell, in pm. (The atomic mass of iron is 55.85 amu. Also, 1 amu = 1.661 × 10-24 g.)

Accepted Answer

Question 14

Liquid ammonia boils at -33.4°C and has a heat of vaporization of 23.5 kJ/mol. Calculate its vapor pressure at -50.0°C.

Accepted Answer

The answer of Liquid ammonia boils at -33.4°C and has...

Question 15

The surface tension of water is lowered when a detergent is present in solution.

Accepted Answer

A) True 
 B)False

Question 16

The energy gap between the conduction band and the valence band is large for

Accepted Answer

A)  conductors. 
B)  semiconductors. 
C)  superconductors. 
D)  insulators. 
E)  alloys. 
A)  conductors. 
B)  semiconductors. 
C)  superconductors. 
D)  insulators. 
E)  alloys.

Question 17

The density of solid sodium chloride, NaCl, is 2.17 g/cm3. Use your knowledge of the sodium chloride lattice to calculate the spacing between Na+ and Cl- nearest neighbors, in cm.
(Atomic masses (amu) are: Na, 22.99; Cl, 35.45. Also, 1 amu = 1.661 × 10-24 g)

Accepted Answer

Question 18

Which of the following terms refers to the resistance of a liquid to flow?

Accepted Answer

A)  surface tension 
B)  capillary action 
C)  viscosity 
D)  adhesion 
E)  cohesion 
A)  surface tension 
B)  capillary action 
C)  viscosity 
D)  adhesion 
E)  cohesion

Question 19

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

Accepted Answer

A) True 
 B)False

Question 20

Lead crystallizes in the face-centered cubic lattice. What is the coordination number for Pb?

Accepted Answer

A)  4 
B)  6 
C)  8 
D)  10 
E)  12 
A)  4 
B)  6 
C)  8 
D)  10 
E)  12

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

Which of the following properties measures the energy needed to increase the surface area of a liquid?

How do the electrical properties of semiconductors differ from those of metals?

Polonium crystallizes in the simple cubic lattice. What is the coordination number for Po?

Select the pair of substances in which the one with the lower vapor pressure at a given temperature is listed first.

Which of the following liquid substances would you expect to have the lowest surface tension?

Which of the following atoms should have the greatest polarizability?

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

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

Octane has a vapor pressure of 40. torr at 45.1°C and 400. torr at 104.0°C. What is its heat of vaporization?

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

Draw a fully labeled phase diagram (P versus T) of a substance whose solid phase can melt due to applied pressure (i.e., solid is less dense than liquid). Clearly label the triple point and the critical temperature on your diagram.

Consider the following phase diagram and identify the process occurring as one goes from point C to point D.

Iron has a body-centered cubic unit cell, and a density of 7.87 g/cm3. Calculate the edge length of the unit cell, in pm. (The atomic mass of iron is 55.85 amu. Also, 1 amu = 1.661 × 10-24 g.)

Liquid ammonia boils at -33.4°C and has a heat of vaporization of 23.5 kJ/mol. Calculate its vapor pressure at -50.0°C.

The surface tension of water is lowered when a detergent is present in solution.

The energy gap between the conduction band and the valence band is large for

The density of solid sodium chloride, NaCl, is 2.17 g/cm3. Use your knowledge of the sodium chloride lattice to calculate the spacing between Na+ and Cl- nearest neighbors, in cm. (Atomic masses (amu) are: Na, 22.99; Cl, 35.45. Also, 1 amu = 1.661 × 10-24 g)

Which of the following terms refers to the resistance of a liquid to flow?

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

Lead crystallizes in the face-centered cubic lattice. What is the coordination number for Pb?

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

The 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: Bonding, Structure, and Reactivity

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

Iron has a body-centered cubic unit cell, and a density of 7.87 g/cm³. Calculate the edge length of the unit cell, in pm. (The atomic mass of iron is 55.85 amu. Also, 1 amu = 1.661 × 10^-24 g.)

The density of solid sodium chloride, NaCl, is 2.17 g/cm³. Use your knowledge of the sodium chloride lattice to calculate the spacing between Na⁺ and Cl^- nearest neighbors, in cm. (Atomic masses (amu) are: Na, 22.99; Cl, 35.45. Also, 1 amu = 1.661 × 10^-24 g)