Question 1

A Born-Haber cycle applied to the formation reaction of an ionic solid

Accepted Answer

A) is normally used to calculate ionization energy. 
B) is normally used to calculate electron affinity. 
C) is normally used to calculate bond energy. 
D) is normally used to determine the overall enthalpy change. 
E) is an application of Hess's Law. 
A) is normally used to calculate ionization energy. 
B) is normally used to calculate electron affinity. 
C) is normally used to calculate bond energy. 
D) is normally used to determine the overall enthalpy change. 
E) is an application of Hess's Law.

Question 2

Arrange aluminum, boron, nitrogen, and phosphorous in order of increasing electronegativity.

Accepted Answer

A) Al<B<P<N 
B) B<Al<N<P 
C) Al<N<P<B 
D) N<P<B<Al 
E) None of these choices are correct. 
A) Al<B<P<N 
B) B<Al<N<P 
C) Al<N<P<B 
D) N<P<B<Al 
E) None of these choices are correct.

Question 3

The more C-O and O-H bonds there are in a substance, the greater will be the amount of heat released when a fixed mass of the substance is burned.

Accepted Answer

A) True 
 B)False

Question 4

As a measure of the strength of metallic bonding, the boiling point of a metal is a better indicator than its melting point.

Accepted Answer

A) True 
 B)False

Question 5

Which of the following elements is the least electronegative?

Accepted Answer

A) Si 
B) Se 
C) S 
D) Sc 
E) Sr 
A) Si 
B) Se 
C) S 
D) Sc 
E) Sr

Question 6

Bond energy increases as bond order increases, for bonding between a given pair of atoms.

Accepted Answer

A) True 
 B)False

Question 7

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) CCl 4 
D) I 2 
E) Ga 
A) NaCl 
B) Si 
C) CCl 4 
D) I 2 
E) Ga

Question 8

For which of the following elements (in their normal, stable, forms) would it be correct to describe the bonding as involving "electron pooling"?

Accepted Answer

A) Hydrogen 
B) Helium 
C) Sulfur 
D) Iodine 
E) Aluminum 
A) Hydrogen 
B) Helium 
C) Sulfur 
D) Iodine 
E) Aluminum

Question 9

Calculate the lattice energy of magnesium sulfide from the data given below. Mg(s) → Mg(g) ΔH° = 148 kJ/mol
Mg(g) → Mg2+(g) + 2e− ΔH° = 2186 kJ/mol
S8(s) → 8S(g) ΔH° = 2232 kJ/mol
S(g) + 2e− → S2−(g) ΔH° = 450 kJ/mol
8Mg(s) + S8(s) → 8MgS(s) ΔH° = −2744 kJ/mol
Mg2+(g) + S2−(g) → MgS(s) ΔH°lattice = ?

Accepted Answer

A) −3406 kJ/mol 
B) −2720. kJ/mol 
C) 2720. kJ/mol 
D) 3406 kJ/mol 
E) None of these choices are correct. 
A) −3406 kJ/mol 
B) −2720. kJ/mol 
C) 2720. kJ/mol 
D) 3406 kJ/mol 
E) None of these choices are correct.

Question 10

The electrostatic energy of two charged particles is inversely proportional to the square of the distance between them.

Accepted Answer

A) True 
 B)False

Question 11

The stronger the bonds in a fuel, the more energy it will yield.

Accepted Answer

A) True 
 B)False

Question 12

Arrange the following bonds in order of increasing bond strength.

Accepted Answer

A) C-I < C-Br < C-Cl < C-F 
B) C-F < C-Cl < C-Br < C-I 
C) C-Br < C-I < C-Cl < C-F 
D) C-I < C-Br < C-F< C-Cl 
E) None of these choices are correct. 
A) C-I < C-Br < C-Cl < C-F 
B) C-F < C-Cl < C-Br < C-I 
C) C-Br < C-I < C-Cl < C-F 
D) C-I < C-Br < C-F< C-Cl 
E) None of these choices are correct.

Question 13

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) H 2O 
B) LiI 
C) CaO 
D) RbF 
E) HCl 
A) H 2O 
B) LiI 
C) CaO 
D) RbF 
E) HCl

Question 14

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 these choices are 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 these choices are correct.

Question 15

Covalently bonded substances do not necessarily exist as separate molecules.

Accepted Answer

A) True 
 B)False

Question 16

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 17

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change ΔH° for the reaction written below, using the bond energies given. N2(g) + 3H2(g) → 2NH3(g)

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 18

In which of these substances are the atoms held together by polar covalent bonding?

Accepted Answer

A) SrCl 2 
B) CsCl 
C) ClF 
D) TiF 2 
E) S 8 
A) SrCl 2 
B) CsCl 
C) ClF 
D) TiF 2 
E) S 8

Question 19

No real bonds are 100% ionic in character.

Accepted Answer

A) True 
 B)False

Question 20

The electrostatic energy of two charged particles is inversely proportional to the distance between them.

Accepted Answer

A) True 
 B)False

Exam 9: Models of Chemical Bonding

A Born-Haber cycle applied to the formation reaction of an ionic solid

Arrange aluminum, boron, nitrogen, and phosphorous in order of increasing electronegativity.

The more C-O and O-H bonds there are in a substance, the greater will be the amount of heat released when a fixed mass of the substance is burned.

As a measure of the strength of metallic bonding, the boiling point of a metal is a better indicator than its melting point.

Which of the following elements is the least electronegative?

Bond energy increases as bond order increases, for bonding between a given pair of atoms.

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?

For which of the following elements (in their normal, stable, forms) would it be correct to describe the bonding as involving "electron pooling"?

The electrostatic energy of two charged particles is inversely proportional to the square of the distance between them.

The stronger the bonds in a fuel, the more energy it will yield.

Arrange the following bonds in order of increasing bond strength.

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

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

Covalently bonded substances do not necessarily exist as separate molecules.

Electronegativity is a measure of

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change ΔH° for the reaction written below, using the bond energies given. N2(g) + 3H2(g) → 2NH3(g)

In which of these substances are the atoms held together by polar covalent bonding?

No real bonds are 100% ionic in character.

The electrostatic energy of two charged particles is inversely proportional to the distance between them.

Keys to the Study of Chemistry: Definitions, Units, and Problem Solving

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

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

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 Reaction Direction

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ) the standard enthalpy change ΔH° for the reaction written below, using the bond energies given. N₂(g) + 3H₂(g) → 2NH₃(g)