Question 1

A double covalent bond contains

Accepted Answer

A)  0 pairs of protons. 
B)  1 pair of electrons. 
C)  2 pairs of electrons. 
D)  2 pairs of protons. 
E)  4 pairs of protons. 
A)  0 pairs of protons. 
B)  1 pair of electrons. 
C)  2 pairs of electrons. 
D)  2 pairs of protons. 
E)  4 pairs of protons. C

Question 2

Use the bond energies provided to estimate ΔH°rxn for the reaction below. C2H4(g)+ H2(g)→ C2H6(g)ΔH°rxn = ?
Bond Bond Energy (kJ/mol)
C-C 347
C-H 414
C=C 611
C≡C 837
H-H 436

Accepted Answer

A)  -128 kJ 
B)  +98 kJ 
C)  +700 kJ 
D)  -102 kJ 
E)  -166 kJ 
A)  -128 kJ 
B)  +98 kJ 
C)  +700 kJ 
D)  -102 kJ 
E)  -166 kJ A

Question 3

Identify the bond with the highest bond energy.

Accepted Answer

A)  Si=O 
B)  N=N 
C)  C=C 
D)  C=N 
E)  O=O 
A)  Si=O 
B)  N=N 
C)  C=C 
D)  C=N 
E)  O=O D

Question 4

Describe the difference between a pure covalent bond and a polar covalent bond.

Accepted Answer

A pure covalent bond occurs when bonding

Question 5

Place the following in order of increasing magnitude of lattice energy. MgO LiI SrO

Accepted Answer

A)  SrO < MgO < LiI 
B)  LiI < SrO < MgO 
C)  MgO < SrO < LiI 
D)  LiI < MgO < SrO 
E)  MgO < LiI < SrO 
A)  SrO < MgO < LiI 
B)  LiI < SrO < MgO 
C)  MgO < SrO < LiI 
D)  LiI < MgO < SrO 
E)  MgO < LiI < SrO

Question 6

Use the data given below to construct a Born-Haber cycle to determine the bond energy of O2. DH°(kJ)
Na(s)→ Na(g)107
Na(g)→ Na⁺(g)+ e⁻ 496
O(g)+ e⁻ → O⁻(g)-141
O⁻(g)+ e⁻ → O2⁻(g)878
2 Na(s)+   O2(g)→ Na2O(s)-416
2 Na⁺(g)+ O2⁻(g)→ Na2O(s)-2608

Accepted Answer

A)  426 kJ 
B)  249 kJ 
C)  852 kJ 
D)  498 kJ 
E)  356 kJ 
A)  426 kJ 
B)  249 kJ 
C)  852 kJ 
D)  498 kJ 
E)  356 kJ

Question 7

Which of the following resonance structures for OCN⁻ will contribute most to the correct structure of OCN⁻?

Accepted Answer

A)  O   C
  N, with two lone pairs on O and two lone pairs on N 
B)  O   C-N, with one lone pair on O and three lone pairs on N 
C)  O   C
  N, with one lone pair on O, two lone pairs on C, and one lone pair on N 
D)  O-C   N, with three lone pairs on O and one lone pair on N 
E)  They all contribute equally to the correct structure of OCN⁻. 
A)  O   C
  N, with two lone pairs on O and two lone pairs on N 
B)  O   C-N, with one lone pair on O and three lone pairs on N 
C)  O   C
  N, with one lone pair on O, two lone pairs on C, and one lone pair on N 
D)  O-C   N, with three lone pairs on O and one lone pair on N 
E)  They all contribute equally to the correct structure of OCN⁻.

Question 8

Which ionic compound would be expected to have the highest lattice energy?

Accepted Answer

A)  Na Cl 
B)  CaO  
C)  Ga2O3 
D)  CO2 
A)  Na Cl 
B)  CaO  
C)  Ga2O3 
D)  CO2

Question 9

Explain why the lattice energy of MgS is approximately 4 times as large as that of NaCl.

Accepted Answer

The Mg²⁺ and Na⁺ ion are similar in size

Question 10

Rank the following molecules in decreasing bond energy. Cl2 Br2 F2 I2

Accepted Answer

A)  I2 > Br2 > Cl2  > F2 
B)  Cl2 > Br2 > F2  > I2 
C)  I2 > Cl2 > Br2  > F2 
D)  Cl2 > I2 > F2  > Br2 
A)  I2 > Br2 > Cl2  > F2 
B)  Cl2 > Br2 > F2  > I2 
C)  I2 > Cl2 > Br2  > F2 
D)  Cl2 > I2 > F2  > Br2

Question 11

Which of the following represents the Lewis structure for Ca2⁺?

Accepted Answer

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

Question 12

Use Lewis theory to determine the chemical formula for the compound formed between Li and Cl.

Accepted Answer

A)  LiCl2 
B)  Li 2Cl 
C)  Li Cl 
D)  Li 2Cl2 
A)  LiCl2 
B)  Li 2Cl 
C)  Li Cl 
D)  Li 2Cl2

Question 13

Identify the bond with the highest bond energy.

Accepted Answer

A)  C≡O 
B)  C≡C 
C)  C≡N 
D)  N≡N 
A)  C≡O 
B)  C≡C 
C)  C≡N 
D)  N≡N

Question 14

Identify the substance that conducts electricity.

Accepted Answer

A)  KBr dissolved in water 
B)  solid KBr 
C)  rubbing alcohol 
D)  solid baking soda 
E)  sugar dissolved in water. 
A)  KBr dissolved in water 
B)  solid KBr 
C)  rubbing alcohol 
D)  solid baking soda 
E)  sugar dissolved in water.

Question 15

Choose the best Lewis structure for SeO42⁻.

Accepted Answer

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

Question 16

Identify the number of bonding pairs and lone pairs of electrons in O2.

Accepted Answer

A)  5 bonding pairs and 5 lone pairs 
B)  4 bonding pair and 2 lone pairs 
C)  2 bonding pairs and 4 lone pairs 
D)  2 bonding pairs and 1 lone pair 
E)  2 bonding pairs and 6 lone pairs 
A)  5 bonding pairs and 5 lone pairs 
B)  4 bonding pair and 2 lone pairs 
C)  2 bonding pairs and 4 lone pairs 
D)  2 bonding pairs and 1 lone pair 
E)  2 bonding pairs and 6 lone pairs

Question 17

Which of the following processes is endothermic?

Accepted Answer

A)  the reaction associated with the lattice energy of LiI. 
B)  the reaction associated with the ionization energy of potassium. 
C)  the reaction associated with the heat of formation of SrO. 
D)  the formation of CO2 from its elements in their standard states. 
E)  None of the above is endothermic. 
A)  the reaction associated with the lattice energy of LiI. 
B)  the reaction associated with the ionization energy of potassium. 
C)  the reaction associated with the heat of formation of SrO. 
D)  the formation of CO2 from its elements in their standard states. 
E)  None of the above is endothermic.

Question 18

Define bond energy.

Accepted Answer

A)  energy required to form 1 mole of the bond in the solid phase 
B)  energy required to form 1 mole of the bond in the gas phase 
C)  energy required to break 1 mole of the bond in the liquid phase 
D)  energy required to break 1 mole of the bond in the gas phase 
E)  energy required to break 1 mole of the bond in the solid phase 
A)  energy required to form 1 mole of the bond in the solid phase 
B)  energy required to form 1 mole of the bond in the gas phase 
C)  energy required to break 1 mole of the bond in the liquid phase 
D)  energy required to break 1 mole of the bond in the gas phase 
E)  energy required to break 1 mole of the bond in the solid phase

Question 19

Identify the property of metals that is NOT explained by the electron sea model.

Accepted Answer

A)  metals conduct heat 
B)  metals conduct electricity 
C)  malleability of metals 
D)  most metals are liquids 
E)  ductility of metals 
A)  metals conduct heat 
B)  metals conduct electricity 
C)  malleability of metals 
D)  most metals are liquids 
E)  ductility of metals

Question 20

Use the bond energies provided to estimate ΔH°rxn for the reaction below. XeF2 + 2 F2 → XeF6 ΔH°rxn = ?
Bond Bond Energy (kJ/mol)
Xe-F 147
F-F 159

Accepted Answer

A)  -429 kJ 
B)  +159 kJ 
C)  -660 kJ 
D)  +176 kJ 
E)  -270 kJ 
A)  -429 kJ 
B)  +159 kJ 
C)  -660 kJ 
D)  +176 kJ 
E)  -270 kJ

Exam 9: Chemical Bonding I: Lewis Theory

A double covalent bond contains

Use the bond energies provided to estimate ΔH°rxn for the reaction below. C2H4(g)+ H2(g)→ C2H6(g)ΔH°rxn = ? Bond Bond Energy (kJ/mol) C-C 347 C-H 414 C=C 611 C≡C 837 H-H 436

Identify the bond with the highest bond energy.

Describe the difference between a pure covalent bond and a polar covalent bond.

Place the following in order of increasing magnitude of lattice energy. MgO LiI SrO

Use the data given below to construct a Born-Haber cycle to determine the bond energy of O2. DH°(kJ) Na(s)→ Na(g)107 Na(g)→ Na⁺(g)+ e⁻ 496 O(g)+ e⁻ → O⁻(g)-141 O⁻(g)+ e⁻ → O2⁻(g)878 2 Na(s)+ O2(g)→ Na2O(s)-416 2 Na⁺(g)+ O2⁻(g)→ Na2O(s)-2608

Which of the following resonance structures for OCN⁻ will contribute most to the correct structure of OCN⁻?

Which ionic compound would be expected to have the highest lattice energy?

Explain why the lattice energy of MgS is approximately 4 times as large as that of NaCl.

Rank the following molecules in decreasing bond energy. Cl2 Br2 F2 I2

Which of the following represents the Lewis structure for Ca2⁺?

Use Lewis theory to determine the chemical formula for the compound formed between Li and Cl.

Identify the bond with the highest bond energy.

Identify the substance that conducts electricity.

Choose the best Lewis structure for SeO42⁻.

Identify the number of bonding pairs and lone pairs of electrons in O2.

Which of the following processes is endothermic?

Define bond energy.

Identify the property of metals that is NOT explained by the electron sea model.

Use the bond energies provided to estimate ΔH°rxn for the reaction below. XeF2 + 2 F2 → XeF6 ΔH°rxn = ? Bond Bond Energy (kJ/mol) Xe-F 147 F-F 159

Matter, measurement, and Problem Solving

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Molecules,compounds,and Chemical Equations

Chemical Quantities and Aqueous Reactions

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding Ii: Molecular Shapes,valence Bond Theory,

Liquids,solids,and Intermolecular Forces

Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Biochemistry

Chemistry of the Nonmetals

Metals and Metallurgy

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Use the bond energies provided to estimate ΔH°_rxn for the reaction below. C₂H₄(g)+ H₂(g)→ C₂H₆(g)ΔH°_rxn= ? Bond Bond Energy (kJ/mol) C-C 347 C-H 414 C=C 611 C≡C 837 H-H 436

Use the data given below to construct a Born-Haber cycle to determine the bond energy of O₂. DH°(kJ) Na(s)→ Na(g)107 Na(g)→ Na⁺(g)+ e⁻ 496 O(g)+ e⁻ → O⁻(g)-141 O⁻(g)+ e⁻ → O²⁻(g)878 2 Na(s)+ O₂(g)→ Na₂O(s)-416 2 Na⁺(g)+ O²⁻(g)→ Na₂O(s)-2608

Rank the following molecules in decreasing bond energy. Cl₂ Br₂ F₂ I₂

Which of the following represents the Lewis structure for Ca²⁺?

Choose the best Lewis structure for SeO₄²⁻.

Identify the number of bonding pairs and lone pairs of electrons in O₂.

Use the bond energies provided to estimate ΔH°_rxn for the reaction below. XeF_{2 +}2 F₂ → XeF₆ ΔH°_rxn= ? Bond Bond Energy (kJ/mol) Xe-F 147 F-F 159