Question 1

The lattice energy of large ions is greater in magnitude than that of small ions of the same charge.

Accepted Answer

A) True 
 B)False

Question 2

Electronegativity is a measure of

Accepted Answer

A)  the energy needed to remove an electron from an atom. 
B)  the energy released when an electron is added to an atom. 
C)  the magnitude of the negative charge on an electron. 
D)  the attraction by an atom for electrons in a chemical bond. 
E)  the magnitude of the negative charge on a molecule. 
A)  the energy needed to remove an electron from an atom. 
B)  the energy released when an electron is added to an atom. 
C)  the magnitude of the negative charge on an electron. 
D)  the attraction by an atom for electrons in a chemical bond. 
E)  the magnitude of the negative charge on a molecule.

Question 3

Select the strongest bond in the following group.

Accepted Answer

A)  C-S 
B)  C-O 
C)  C=C 
D)  CF1F1F1S1F1F1F10N 
E)  C-F 
A)  C-S 
B)  C-O 
C)  C=C 
D)  CF1F1F1S1F1F1F10N 
E)  C-F

Question 4

Which one of the following properties is least characteristic of substances composed of small, covalently-bonded molecules?

Accepted Answer

A)  low melting point 
B)  low boiling point 
C)  weak bonds 
D)  poor electrical conductor when solid 
E)  poor electrical conductor when molten 
A)  low melting point 
B)  low boiling point 
C)  weak bonds 
D)  poor electrical conductor when solid 
E)  poor electrical conductor when molten

Question 5

Based on electronegativity trends in the periodic table, predict which of the following compounds will have the greatest % ionic character in its bonds.

Accepted Answer

A)  H2O 
B)  LiI 
C)  CaO 
D)  RbF 
E)  HCl 
A)  H2O 
B)  LiI 
C)  CaO 
D)  RbF 
E)  HCl

Question 6

In covalent bond formation, the potential energy reaches a maximum when the internuclear distance is equal to the bond length.

Accepted Answer

A) True 
 B)False

Question 7

Which one of the following properties is least characteristic of typical ionic compounds?

Accepted Answer

A)  high melting point 
B)  high boiling point 
C)  brittleness 
D)  poor electrical conductor when solid 
E)  poor electrical conductor when molten 
A)  high melting point 
B)  high boiling point 
C)  brittleness 
D)  poor electrical conductor when solid 
E)  poor electrical conductor when molten

Question 8

Describe, with appropriate explanations, the key factors which affect the magnitude of the lattice energy of an ionic substance.

Accepted Answer

By Coulomb's law, the energy of two elec

Question 9

No real bonds are 100% ionic in character.

Accepted Answer

A) True 
 B)False

Question 10

In not more than three sentences, describe the electron arrangement responsible for bonding in Cl2 molecules.

Accepted Answer

This is covalent bonding. The chlorine a

Question 11

Arrange oxygen, sulfur, calcium, rubidium, and potassium in order of decreasing electronegativity.

Accepted Answer

A)  O > S > Ca > K > Rb 
B)  O > S > Ca > Rb > K 
C)  O > S > Rb > K > Ca 
D)  O > S > Rb > Ca > K 
E)  None of the above orders is correct. 
A)  O > S > Ca > K > Rb 
B)  O > S > Ca > Rb > K 
C)  O > S > Rb > K > Ca 
D)  O > S > Rb > Ca > K 
E)  None of the above orders is correct.

Question 12

Describe in brief how electronegativity values can be used to predict the percent ionic character of a bond between two atoms.

Accepted Answer

Take the electronegativity difference (F

Question 13

The lattice energy is the energy released when separated ions in the gas phase combine to form ionic molecules in the gas phase.

Accepted Answer

A) True 
 B)False

Question 14

Select the compound with the highest (i.e., most negative) lattice energy.

Accepted Answer

A)  CaS(s) 
B)  BaO(s) 
C)  NaI(s) 
D)  LiBr(s) 
E)  MgO(s) 
A)  CaS(s) 
B)  BaO(s) 
C)  NaI(s) 
D)  LiBr(s) 
E)  MgO(s)

Question 15

In not more than three sentences, describe the key features of bonding in solid aluminum.

Accepted Answer

This is metallic bonding. The aluminum a

Question 16

When two atoms form a covalently-bonded diatomic molecule, the distance between the nuclei at which the potential energy is at a minimum is called

Accepted Answer

A)  the bond energy. 
B)  the bond length. 
C)  the molecular diameter. 
D)  the covalent radius. 
E)  the covalent diameter. 
A)  the bond energy. 
B)  the bond length. 
C)  the molecular diameter. 
D)  the covalent radius. 
E)  the covalent diameter.

Question 17

Analysis of an unknown substance showed that it has a moderate melting point and is a good conductor of heat and electricity in the solid phase. Which of the following substances would have those characteristics?

Accepted Answer

A)  NaCl 
B)  Si 
C)  CCl4 
D)  I2 
E)  Ga 
A)  NaCl 
B)  Si 
C)  CCl4 
D)  I2 
E)  Ga

Question 18

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change F1F1F1S1F1F1F10H° for the reaction written below, using the bond energies given.

Accepted Answer

A)  -969 kJ 
B)  -204 kJ 
C)  -105 kJ 
D)  204 kJ 
E)  595 kJ 
A)  -969 kJ 
B)  -204 kJ 
C)  -105 kJ 
D)  204 kJ 
E)  595 kJ

Question 19

Which of the following elements is the most electronegative?

Accepted Answer

A)  S 
B)  Ru 
C)  Si 
D)  Te 
E)  Cs 
A)  S 
B)  Ru 
C)  Si 
D)  Te 
E)  Cs

Question 20

Which one of the following properties is least characteristic of typical metals?

Accepted Answer

A)  moderately high melting point 
B)  high boiling point 
C)  brittleness 
D)  good electrical conductor when solid 
E)  good electrical conductor when molten 
A)  moderately high melting point 
B)  high boiling point 
C)  brittleness 
D)  good electrical conductor when solid 
E)  good electrical conductor when molten

Exam 9: Models of Chemical Bonding

The lattice energy of large ions is greater in magnitude than that of small ions of the same charge.

Electronegativity is a measure of

Select the strongest bond in the following group.

Which one of the following properties is least characteristic of substances composed of small, covalently-bonded molecules?

Based on electronegativity trends in the periodic table, predict which of the following compounds will have the greatest % ionic character in its bonds.

In covalent bond formation, the potential energy reaches a maximum when the internuclear distance is equal to the bond length.

Which one of the following properties is least characteristic of typical ionic compounds?

Describe, with appropriate explanations, the key factors which affect the magnitude of the lattice energy of an ionic substance.

No real bonds are 100% ionic in character.

In not more than three sentences, describe the electron arrangement responsible for bonding in Cl2 molecules.

Arrange oxygen, sulfur, calcium, rubidium, and potassium in order of decreasing electronegativity.

Describe in brief how electronegativity values can be used to predict the percent ionic character of a bond between two atoms.

The lattice energy is the energy released when separated ions in the gas phase combine to form ionic molecules in the gas phase.

Select the compound with the highest (i.e., most negative) lattice energy.

In not more than three sentences, describe the key features of bonding in solid aluminum.

When two atoms form a covalently-bonded diatomic molecule, the distance between the nuclei at which the potential energy is at a minimum is called

Analysis of an unknown substance showed that it has a moderate melting point and is a good conductor of heat and electricity in the solid phase. Which of the following substances would have those characteristics?

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change H° for the reaction written below, using the bond energies given.

Which of the following elements is the most electronegative?

Which one of the following properties is least characteristic of typical metals?

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

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

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

In not more than three sentences, describe the electron arrangement responsible for bonding in Cl₂ molecules.