Question 1

The strongest intermolecular interactions between ethyl alcohol (CH3CH2OH) molecules arise from

Accepted Answer

A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  ion-dipole interactions. 
E)  carbon-oxygen bonds. 
A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  ion-dipole interactions. 
E)  carbon-oxygen bonds.

Question 2

Iron crystallizes in the body-centered cubic lattice. What is the coordination number for Fe?

Accepted Answer

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

Question 3

Hexagonal close packing of identical atoms occurs when close-packed layers are stacked in an abcabc.... arrangement.

Accepted Answer

A) True 
 B)False

Question 4

Chlorine trifluoride is used in processing nuclear reactor fuel. It has a vapor pressure of 29.1 torr at -47.0°C and its heat of vaporization is 30.61 kJ/mol. At what temperature would its vapor pressure be 107.7 torr?

Accepted Answer

The answer of Chlorine trifluoride is used in processing nuclear...

Question 5

Liquid sodium can be used as a heat transfer fluid. Its vapor pressure is 40.0 torr at 633°C and 400.0 torr at 823°C. Calculate its heat of vaporization.

Accepted Answer

A)  43.4 kJ/mol 
B)  52.5 kJ/mol 
C)  70.6 kJ/mol 
D)  1.00 × 102 kJ/mol 
E)  none of the above 
A)  43.4 kJ/mol 
B)  52.5 kJ/mol 
C)  70.6 kJ/mol 
D)  1.00 × 102 kJ/mol 
E)  none of the above

Question 6

Which of the following pairs of molecules can form hydrogen bonds between them?

Accepted Answer

A)  HCl and HI 
B)  CH3OH and NH3 
C)  CH4 and H2O 
D)  SO2 and CH2O 
E)  H2 and O2 
A)  HCl and HI 
B)  CH3OH and NH3 
C)  CH4 and H2O 
D)  SO2 and CH2O 
E)  H2 and O2

Question 7

Which of the following factors contributes to a low viscosity for a liquid?

Accepted Answer

A)  low temperature 
B)  spherical molecular shape 
C)  hydrogen bonding 
D)  high molecular weight 
E)  high boiling point 
A)  low temperature 
B)  spherical molecular shape 
C)  hydrogen bonding 
D)  high molecular weight 
E)  high boiling point

Question 8

If the solid form of a pure substance is denser than its liquid form, an increase in pressure will cause the melting point to decrease.

Accepted Answer

A) True 
 B)False

Question 9

The strongest intermolecular interactions between hydrogen sulfide (H2S) molecules arise from

Accepted Answer

A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  ion-dipole interactions. 
E)  disulfide linkages. 
A)  dipole-dipole forces. 
B)  London dispersion forces. 
C)  hydrogen bonding. 
D)  ion-dipole interactions. 
E)  disulfide linkages.

Question 10

a. Name the two unit cells which occur in close packing of identical atoms.
b. Briefly explain how the two types of close-packed lattices of identical atoms differ, in terms of atomic arrangements.

Accepted Answer

a. face-centered cubic; hexagonal
b. Cub

Question 11

A metal such with a face-centered cubic lattice will have ________________ atom(s) per unit cell.

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  10 
A)  1 
B)  2 
C)  3 
D)  4 
E)  10

Question 12

Which of the following should 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 13

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° 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° 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 14

In an ionic solid MX consisting of the monatomic ions, M+ and X-, the coordination number of M+ is _______________.

Accepted Answer

A)  1 
B)  2 
C)  6 
D)  8 
E)  impossible to predict without knowing the crystal structure of MX 
A)  1 
B)  2 
C)  6 
D)  8 
E)  impossible to predict without knowing the crystal structure of MX

Question 15

Assuming that atoms are spherical, calculate the fraction of space which is occupied by atoms (i.e., the packing efficiency) in a metal with a simple cubic unit cell.

Accepted Answer

The answer of Assuming that atoms are spherical, calculate the...

Question 16

A certain solid metallic element has a density 7.87 g/cm3 and a molar mass of 55.85 g/mol. It crystallizes with a cubic unit cell, with an edge length of 286.7 pm. Calculate the number of atoms per unit cell.

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  6 
A)  1 
B)  2 
C)  3 
D)  4 
E)  6

Question 17

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

Accepted Answer

A)  CCl4, CI4 
B)  H2O, H2Se 
C)  C6H14, C4H10 
D)  NH3, NF3 
E)  none of the above 
A)  CCl4, CI4 
B)  H2O, H2Se 
C)  C6H14, C4H10 
D)  NH3, NF3 
E)  none of the above

Question 18

Which one of the following quantities is generally not obtainable from a single heating or cooling curve of a substance, measured at atmospheric pressure?

Accepted Answer

A)  melting point 
B)  boiling point 
C)  triple point 
D)  heat of fusion 
E)  heat of vaporization 
A)  melting point 
B)  boiling point 
C)  triple point 
D)  heat of fusion 
E)  heat of vaporization

Question 19

Consider the phase diagram shown below.   a. What phase(s) is/are present at point A?
b. What phase(s) is/are present at point B?
c. Name point C and explain its significance.
d. Starting at D, if the pressure is lowered while the temperature remains constant, describe what will happen.

Accepted Answer

a. liquid
b. solid, liquid, and gas
c. C

Question 20

Some of the information obtained from the heating or cooling curve of a substance can also be found on a phase diagram of that substance.

Accepted Answer

A) True 
 B)False

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

The strongest intermolecular interactions between ethyl alcohol (CH3CH2OH) molecules arise from

Iron crystallizes in the body-centered cubic lattice. What is the coordination number for Fe?

Hexagonal close packing of identical atoms occurs when close-packed layers are stacked in an abcabc.... arrangement.

Chlorine trifluoride is used in processing nuclear reactor fuel. It has a vapor pressure of 29.1 torr at -47.0°C and its heat of vaporization is 30.61 kJ/mol. At what temperature would its vapor pressure be 107.7 torr?

Liquid sodium can be used as a heat transfer fluid. Its vapor pressure is 40.0 torr at 633°C and 400.0 torr at 823°C. Calculate its heat of vaporization.

Which of the following pairs of molecules can form hydrogen bonds between them?

Which of the following factors contributes to a low viscosity for a liquid?

If the solid form of a pure substance is denser than its liquid form, an increase in pressure will cause the melting point to decrease.

The strongest intermolecular interactions between hydrogen sulfide (H2S) molecules arise from

a. Name the two unit cells which occur in close packing of identical atoms. b. Briefly explain how the two types of close-packed lattices of identical atoms differ, in terms of atomic arrangements.

A metal such with a face-centered cubic lattice will have ________________ atom(s) per unit cell.

Which of the following should have the highest boiling point?

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

In an ionic solid MX consisting of the monatomic ions, M+ and X-, the coordination number of M+ is _______________.

Assuming that atoms are spherical, calculate the fraction of space which is occupied by atoms (i.e., the packing efficiency) in a metal with a simple cubic unit cell.

A certain solid metallic element has a density 7.87 g/cm3 and a molar mass of 55.85 g/mol. It crystallizes with a cubic unit cell, with an edge length of 286.7 pm. Calculate the number of atoms per unit cell.

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

Which one of the following quantities is generally not obtainable from a single heating or cooling curve of a substance, measured at atmospheric pressure?

Consider the phase diagram shown below. a. What phase(s) is/are present at point A? b. What phase(s) is/are present at point B? c. Name point C and explain its significance. d. Starting at D, if the pressure is lowered while the temperature remains constant, describe what will happen.

Some of the information obtained from the heating or cooling curve of a substance can also be found on a phase diagram of that substance.

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

The strongest intermolecular interactions between ethyl alcohol (CH₃CH₂OH) molecules arise from

The strongest intermolecular interactions between hydrogen sulfide (H₂S) molecules arise from

In an ionic solid MX consisting of the monatomic ions, M⁺and X^-, the coordination number of M⁺is _______________.

A certain solid metallic element has a density 7.87 g/cm³ and a molar mass of 55.85 g/mol. It crystallizes with a cubic unit cell, with an edge length of 286.7 pm. Calculate the number of atoms per unit cell.