59) Draw the best Lewis structure for Cl3⁻. What is the formal charge on the central Cl atom?
A) -1
B) 0
C) +1
D) +2
E) -2
60) Draw the best Lewis structure for the free radical, NO2. What is the formal charge on the N?
A) 0
B) +1
C) -1
D) +2
E) -2
61) Draw the best Lewis structure for CH3-1. What is the formal charge on the C?
A) 0
B) 1
C) -1
D) 2
62) Draw the best Lewis structure for CH3+1. What is the formal charge on the C?
A) 0
B) 1
C) -1
D) 2
63) Draw the best Lewis structure for BrO4⁻ and determine the formal charge on bromine.
A) -1
B) +1
C) 0
D) +2
E) +3
64) Identify the compound with atoms that have an incomplete octet.
A) ICl5
B) CO2
C) BF3
D) Cl2
E) CO
65) Which compound has the longest carbon-carbon bond length?
A) CH3CH3
B) CH2CH2
C) HCCH
D) all bond lengths are the same
66) Which compound has the shortest carbon-carbon bond length?
A) CH3CH3
B) CH2CH2
C) HCCH
D) all bond lengths are the same
67) Which compound has the highest carbon-carbon bond strength?
A) CH3CH3
B) CH2CH2
C) HCCH
D) all bond strengths are the same
68) Place the following in order of increasing bond length.
C-F C-S C-Cl
A) C-S < C-Cl < C-F
B) C-Cl < C-F < C-S
C) C-F < C-S < C-Cl
D) C-F < C-Cl < C-S
E) C-S < C-F < C-Cl
69) Place the following in order of decreasing bond length.
H-F H-I H-Br
A) H-F > H-Br > H-I
B) H-I > H-F > H-Br
C) H-I > H-Br > H-F
D) H-Br > H-F > H-I
E) H-F > H-I > H-Br
70) Place the following in order of decreasing XO bond length, where “X” represents the central atom
in each of the following compounds or ions.
SiO32⁻ CO2 CO32⁻
A) CO2 > SiO32⁻ > CO32⁻
B) CO2 > CO32⁻ > SiO32⁻
C) CO32⁻ > CO2 > SiO32⁻
D) CO32⁻ > SiO32⁻ > CO2
E) SiO32⁻ > CO32⁻ > CO2
71) Place the following in order of increasing bond length.
NO2⁻ NO3⁻ NO
A) NO < NO2⁻ < NO3⁻
B) NO2⁻ < NO3⁻ < NO
C) NO3⁻ < NO < NO2⁻
D) NO < NO3⁻ < NO2⁻
E) NO3⁻ < NO2⁻ < NO
72) Rank the following molecules in decreasing bond energy.
Cl2 Br2 F2 I2
A) I2 > Br2 > Cl2 > F2
B) Cl2 > Br2 > F2 > I2
C) I2 > Cl2 > Br2 > F2
D) Cl2 > I2 > F2 > Br2
73) Identify the bond with the highest bond energy.
A) Si=O
B) N=N
C) C=C
D) C=N
E) O=O
74) Which of the following processes are exothermic?
A) Cl2(g) → 2Cl(g)
B) Br(g) + e⁻ → Br⁻(g)
C) Li(s) → Li(g)
D) NaF(s) → Na⁺(g) + F⁻(g)
E) None of the above are exothermic.
75) Which of the following processes are exothermic?
A) the second ionization energy of Mg
B) the sublimation of Li
C) the breaking the bond of I2
D) the formation of NaBr from its constituent elements in their standard state
E) None of the above are exothermic
76) Which of the following processes are endothermic?
A) K⁺(g) + I⁻(g) → KI(s)
B) 2 Br(g) → Br2(g)
C) Ca(s) → Ca(g)
D) 2 Na(s) + O2(g) → Na2O(s)
E) None of the above are endothermic.
77) Which of the following processes are endothermic?
A) the reaction associated with the lattice energy of LiCl.
B) the reaction associated with the ionization energy of potassium.
C) the reaction associated with the heat of formation of CaS.
D) the formation of F2 from its elements in their standard states.
E) None of the above are endothermic.
78) Use the bond energies provided to estimate ΔH°rxn for the reaction below.
PCl3(g) + Cl2(g) → PCl5(l) ΔH°rxn = ?
Bond Bond Energy (kJ/mol)
Cl–Cl 243
P-Cl 331
A) -243 kJ
B) -419 kJ
C) -662 kJ
D) -67 kJ
E) -905 kJ
79) Use the bond energies provided to estimate ΔH°rxn for the reaction below.
2 Br2(l) + C2H2(g) → C2H2Br4(l) ΔH°rxn = ?
Bond Bond Energy (kJ/mol)
Br–Br 193
C≡C 837
C-C 347
C-Br 276
C-H 414
A) +407 kJ
B) -324 kJ
C) -228 kJ
D) +573 kJ
E) -648 kJ
80) Use the bond energies provided to estimate ΔH°rxn for the reaction below.
CH3OH(l) + 2 O2(g) → CO2(g) + 2 H2O(g) ΔH°rxn = ?
Bond Bond Energy (kJ/mol)
C-H 414
C-O 360
C=O 799
O=O 498
O-H 464
A) +473 kJ
B) -91 kJ
C) -486 kJ
D) -392 kJ
E) +206 kJ
81) 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
A) -429 kJ
B) +159 kJ
C) -660 kJ
D) +176 kJ
E) -270 kJ
82) 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
A) -128 kJ
B) +98 kJ
C) +700 kJ
D) -102 kJ
E) -166 kJ
Algorithmic Questions
1) Identify an ionic bond.
A) Electrons are pooled.
B) Electrons are shared.
C) Electrons are transferred.
D) Protons are gained.
E) Electrons are lost.
2) Identify the compound with ionic bonding.
A) NaBr
B) Na
C) H2O
D) He
E) S
3) Identify the compound with covalent bonding.
A) NaBr
B) Na
C) H2O
D) He
E) S
4) Identify the compound with metallic bonding.
A) NaBr
B) Na
C) H2O
D) He
E) S
5) Identify the substance that conducts electricity.
A) NaCl dissolved in water
B) solid NaCl
C) ethanol
D) solid sugar
E) sugar dissolved in water.
6) Use Lewis theory to determine the chemical formula for the compound formed between Ba and N.
A) BaN
B) Ba3N2
C) BaN2
D) Ba2N
E) Ba2N3
7) Use Lewis theory to determine the chemical formula for the compound formed between Na and O.
A) NaO
B) NaO2
C) Na2O
D) Na2O3
E) Na3O2
8) Use Lewis theory to determine the chemical formula for the compound formed between Ba and I.
A) BaI
B) Ba2I3
C) Ba3I2
D) BaI2
E) Ba2I
9) Use Lewis theory to determine the chemical formula for the compound formed between Al and Cl.
A) Al3Cl2
B) Al2Cl3
C) AlCl2
D) AlCl
E) AlCl3
10) Use Lewis theory to determine the chemical formula for the compound formed between Li and Br.
A) LiBr2
B) Li 2Br
C) Li Br
D) Li 2Br2
11) Which of the following ionic compounds would be expected to have the highest lattice energy?
A) LiF
B) LiCl
C) LiBr
D) LiI
12) Which of the following ionic compounds would be expected to have the highest lattice energy?
A) Li Cl
B) Na Cl
C) K Cl
D) Rb Cl
13) Which ionic compound would be expected to have the highest lattice energy?
A) Rb2O
B) SrO
C) In2O3
D) CO2
14) Identify the compound with the highest magnitude of lattice energy.
A) MgCl2
B) BaCl2
C) SrCl2
D) CsCl2
15) Identify the compound with the lowest magnitude of lattice energy.
A) KCl
B) KBr
C) SrO
D) BaO
16) Place the following in order of increasing magnitude of lattice energy.
MgO LiI BaS
A) BaS < MgO < LiI
B) LiI < BaS < MgO
C) MgO < BaS < LiI
D) LiI < MgO < BaS
E) MgO < LiI < BaS
17) Place the following in order of decreasing magnitude of lattice energy.
KF CaS RbI
A) RbI > KF > CaS
B) RbI > CaS > KF
C) CaS > RbI > KF
D) KF > RbI > CaS
E) CaS > KF > RbI
18) Choose the compound below that should have the highest melting point according to the ionic
bonding model.
A) AlN
B) MgO
C) NaCl
D) CaS
E) RbI
19) Choose the compound below that should have the highest melting point according to the ionic
bonding model.
A) SrI2
B) MgF2
C) CaCl2
D) SrF2
E) SrBr2
20) Choose the compound below that should have the lowest melting point according to the ionic
bonding model.
A) LiF
B) LiCl
C) CsI
D) KBr
E) RbI
21) Identify the number of bonding pairs and lone pairs of electrons in N2.
A) 6 bonding pair and 1 lone pair
B) 4 bonding pair and 2 lone pairs
C) 3 bonding pairs and 2 lone pairs
D) 2 bonding pairs and 1 lone pair
E) 2 bonding pairs and 3 lone pairs
22) Of the following elements, which has the highest electronegativity?
A) Si
B) P
C) Ti
D) Ge
23) Of the following elements, which has the lowest electronegativity?
A) Sr
B) I
C) Ba
D) At
24) Place the following elements in order of increasing electronegativity.
Na Rb P
A) P < Na < Rb
B) Na < P < Rb
C) Rb < P < Na
D) Rb < Na < P
E) P < Rb < Na
25) Place the following elements in order of decreasing electronegativity.
S F Se
A) Se > S > F
B) F > Se > S
C) Se > F > S
D) S > F > Se
E) F > S > Se
26) Place the following elements in order of increasing electronegativity.
Ba Se Li
A) Ba < Li < Se
B) Li < Se < Ba
C) Ba < Se < Li
D) Se < Ba < Li
E) Se < Li < Ba
27) List the following compounds in decreasing electronegativity difference.
F2 HF KF
A) KF > F2 > HF
B) F2 > HF > KF
C) HF > KF > F2
D) KF > HF > F2
28) Choose the bond below that is most polar.
A) C-N
B) C-F
C) N-O
D) C-C
E) Cl-Cl
29) Using periodic trends, place the following bonds in order of increasing ionic character.
S-Cl Se–Cl O-Cl
A) Se-Cl < S-Cl < O-Cl
B) S-Cl < Se-Cl < O-Cl
C) O-Cl < Se-Cl < S-Cl
D) Se-Cl < O-Cl < S-Cl
E) O-Cl < S-Cl < Se-Cl
30) Using periodic trends, place the following bonds in order of decreasing ionic character.
Sb-F P-F As-F
A) Sb-F > As-F > P-F
B) As-F > Sb-F > P-F
C) Sb-F > P-F > As-F
D) P-F > As-F > Sb-F
E) Sb-F > P-F > As-F
31) Which molecule or compound below contains a pure covalent bond?
A) Li2CO3
B) SCl6
C) Br2
D) PCl3
E) NaCl
32) Which molecule or compound below contains a polar covalent bond?
A) C2H4
B) ZnS
C) LiI
D) NCl3
E) AgI
33) Which molecule or compound below contains an ionic bond?
A) CO2
B) C2Br4
C) SiF4
D) OCl2
E) NH4NO3
34) The electronegativity is 2.1 for H and 1.9 for Pb. Based on these electronegativities PbH4 would be
expected to
A) be ionic and contain H– ions.
B) be ionic and contain H+ ions.
C) have polar covalent bonds with a partial negative charges on the H atoms.
D) have polar covalent bonds with a partial positive charges on the H atoms.
35) The compound ClF contains
A) ionic bonds.
B) nonpolar covalent bonds.
C) polar covalent bonds with partial negative charges on the F atoms.
D) polar covalent bonds with partial negative charges on the Cl atoms.
36) The phosphorus atom in PCl3 would be expected to have a
A) partial positive (δ+) charge.
B) partial negative (δ-) charge.
C) 3+ charge.
D) 3- charge.
37) The iodine atom in I2 would be expected to have a
A) charge of 1-.
B) partial charge δ-.
C) partial charge δ+.
D) charge of 0.
38) Give the number of valence electrons for SBr4.
A) 28
B) 30
C) 32
D) 34
39) Give the number of pairs of valence electrons for BF3.
A) 16
B) 8
C) 14
D) 10
E) 12
41) Which of the following elements can form compounds with an expanded octet?
A) Se
B) C
C) Li
D) F
E) All of the above elements can form compounds with an expanded octet.
42) Which of the following elements can form compounds with an expanded octet?
A) O
B) Br
C) F
D) Be
E) None of the above can form compounds with an expanded octet.
43) How many of the following elements can form compounds with an expanded octet?
I O Br Xe
A) 2
B) 0
C) 3
D) 1
E) 4
44) How many of the following elements can form compounds with an expanded octet?
P Kr Xe B
A) 0
B) 1
C) 2
D) 3
E) 4
45) How many lone pairs of electrons are on the As atom in AsCl3?
A) 0
B) 1
C) 2
D) 3
46) Which element can expand its valence shell to accommodate more than eight electrons?
A) N
B) O
C) Br
D) He
47) Which of the following contains an atom that does not obey the octet rule?
A) CsI
B) SnO2
C) ClF5
D) ClF
48) How many lone pairs of electrons are on the S atom in SF4 ?
A) 0
B) 1
C) 2
D) 3
49) How many lone pairs are on the Br atom in BrCl2–?
A) 0
B) 1
C) 2
D) 3
50) Choose the bond below that is the strongest.
A) C-F
B) C=O
C) C-I
D) I-I
E) C≡N
51) Choose the bond below that is the strongest.
A) N=O
B) N-F
C) C-O
D) N-C
E) N=N
52) Choose the bond below that is the weakest.
A) Na-Br
B) Br-Br
C) C=N
D) Li-I
E) C=N
53) Choose the bond below that is the weakest.
A) C≡O
B) N≡N
C) C-I
D) C=O
E) K-Br
Matching Questions
Match the following.
A) metallic bond
B) weakest ionic bond
C) strongest covalent bond
D) highest melting point
E) longest covalent bond
1) Sr-Sr
Diff: 1 Page Ref: 9.2
2) Cs-I
Diff: 1 Page Ref: 9.4
3) Ca-O
Diff: 1 Page Ref: 9.4
4) Se-I
Diff: 1 Page Ref: 9.5
5) C=N
Diff: 1 Page Ref: 9.5
39
Short Answer Questions
1) Describe a covalent bond.
2) Draw the Lewis Dot structure for Al3+.
3) Explain why the lattice energy of MgS is approximately 4 times as large as that of NaCl.
4) List the most electronegative atom.
5) List the least electronegative atom.
6) Define dipole moment.
7) How are electron affinity and electronegativity different?
8) Describe the difference between a pure covalent bond and a polar covalent bond.
9) Draw the Lewis structure for the acetate ion, CH3CO2⁻, including any important resonance
structures. Label each atom with its formal charge.
10) Draw the Lewis structure for BrO3–. Make sure to include any important resonance structures.
11) Define formal charge.
12) Define bond energy.