AP Chemistry Practice Test: Chs. 8 &9 - Bonding
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Based on the octet rule, magnesium most likely forms a __________ ion.
A) Mg B) Mg 6+
C) Mg 2+
D) Mg 6-
E) Mg 2-
2) Based on the octet rule, phosphorus most likely forms a __________ ion.
A) P5B) P5+
C) P+
D) P3-
E) P3+
3) Which ion below has a noble gas electron configuration?
A) B2+
B) Be2+
C) C2+
D) N2-
E) Li2+
4) The electron configuration of the phosphide ion (P3-) is __________.
A) [Ne]3s 23p3
B) [Ne]3s 23p1
C) [Ne]3s 2
D) [Ne]3p2
E) [Ne]3s 23p6
5) The halogens, alkali metals, and alkaline earth metals have __________ valence electrons, respectively.
A) 8, 2, and 3
B) 7, 1, and 2
C) 2, 7, and 4
D) 2, 4, and 6
E) 1, 5, and 7
6) Lattice energy is __________.
A) the sum of electron affinities of the components in an ionic solid
B) the energy required to convert a mole of ionic solid into its constituent ions in the gas phase
C) the sum of ionization energies of the components in an ionic solid
D) the energy given off when gaseous ions combine to form one mole of an ionic solid
E) the energy required to produce one mole of an ionic compound from its constituent elements in their
standard states
7) In which of the molecules below is the carbon-carbon distance the shortest?
A) H3C-CH3
B) H-C ”C-H
C) H2ChChCH2
D) H3C-CH2-CH3
E) H2ChCH2
8) Of the atoms below, __________ is the most electronegative.
A) Ca
B) Rb
C) S
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D) Cl
E) Si
9) Electronegativity __________ from left to right within a period and __________ from top to bottom within a
group.
A) increases, increases
B) increases, decreases
C) decreases, increases
D) stays the same, increases
E) increases, stays the same
10) The Lewis structure of AsH3 shows __________ nonbonding electron pair(s) on As.
A) 0
B) 1
C) 2
D) 3
E) This cannot be determined from the data given.
11) The Lewis structure of HCN (H bonded to C) shows that __________ has __________ nonbonding electron
pairs.
A) C, 1
B) N, 2
C) C, 2
D) N, 1
E) H, 1
12) The Lewis structure of N2H2 shows __________.
A) each nitrogen has one nonbinding electron pair
B) each hydrogen has one nonbonding electron pair
C) each nitrogen has two nonbinding electron pairs
D) a nitrogen-nitrogen single bond
E) a nitrogen-nitrogen triple bond
Consider the following species when answering the questions that follow:
(i) PCl3
(ii) CH2Cl2
(iii) HCN
(iv) C2H4
(v) NH3
13) In which Lewis structure does the central atom have a non-zero formal charge?
A) (i)
B) (ii)
C) (iii)
D) (v)
E) none
D) +3
E) +2
14) The formal charge on carbon in the molecule below is __________.
A) 0
B) +1
C) -1
15) How many equivalent resonance forms can be drawn for SO2 without expanding octet on the sulfur atom
(sulfur is the central atom)?
A) 3
B) 0
C) 4
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D) 2
E) 1
For the questions that follow, consider the BEST Lewis structures of the following oxyions:
(i) NO2-
(ii) NO3-
(iii) SO32-
(iv) SO42-
(v) BrO3-
16) The central atoms in __________ cannot expand octet.
A) (i) only
B) (ii) only
C) (i) and (ii)
D) (ii) and (iii)
E) (iii) and (iv)
17) The Lewis structure of __________ cannot be drawn without a non-zero formal charge on the central atom.
A) (i)
B) (ii)
C) (iii)
D) (iv)
E) (v)
18) Lewis structures of which ions can be drawn with and without expanding the octet on the central atom?
A) (i) and (ii)
B) (iii) only
C) (iv) only
D) (iii) and (iv)
E) (iii), (iv), and (v)
19) Lewis structures of which ions can be drawn with all formal charges being zero?
A) all
B) (i) and (ii)
C) (ii) only
D) (iii), (iv), and (v)
E) none
20) The central atom in __________ does not violate the octet rule.
A) KrF2
B) XeF4
C) CF4
D) ICl4-
E) SF4
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
21) The reaction below is used to produce methanol:
CO (g) + 2 H2 (g) ¬ CH3OH (l)
DHrxn = -128 kJ
(a) Calculate the C-H bond energy given the following data:
Bond D (kJ/mol)
C∏O
1072
HπH
436
CπO
358
OπH
463
(b) The tabulated value of the (C-H) bond energy is 413 kJ/mol. Explain why there is a difference between the
number you have calculated in (a) and the tabulated value.
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MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
22) Using the table of average bond energies below, the DH for the reaction is __________ kJ.
H-C”C-H (g) + H-I (g) ¬ H2ChCHI (g)
Bond:
D (kJ/mol):
C”C
839
C=C
614
A) +506
H-I
299
B) -506
C-I
240
C-H
413
C) -129
D) +129
E) -931
23) As the number of covalent bonds between two atoms increases, the distance between the atoms __________ and
the strength of the bond between them __________.
A) increases, increases
B) decreases, decreases
C) increases, decreases
D) decreases, increases
E) is unpredictable
24) According to VSEPR theory, if there are three electron domains in the valence shell of an atom, they will be
arranged in a(n) __________ geometry.
A) trigonal bipyramidal
B) tetrahedral
C) linear
D) octahedral
E) trigonal planar
25) According to VSEPR theory, if there are five electron domains in the valence shell of an atom, they will be
arranged in a(n) __________ geometry.
A) tetrahedral
B) linear
C) octahedral
D) trigonal planar
E) trigonal bipyramidal
26) The electron-domain geometry and molecular geometry of iodine trichloride are __________ and __________,
respectively.
A) T-shaped, trigonal planar
B) trigonal planar, trigonal planar
C) trigonal bipyramidal, T-shaped
D) tetrahedral, trigonal pyramidal
E) octahedral, trigonal planar
27) The molecular geometry of __________ is square planar.
A) CCl4
B) XeF4
C) ICl3
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D) XeF2
E) PH3
28) The molecular geometry of the H3O+ ion is __________.
A) trigonal pyramidal
B) octahedral
C) bent
D) tetrahedral
E) linear
29) The molecular geometry of the CS2 molecule is __________.
A) tetrahedral
B) T-shaped
C) bent
D) trigonal planar
E) linear
30) The molecular geometry of the PF4+ ion is __________.
A) trigonal bipyramidal
B) tetrahedral
C) trigonal pyramidal
D) octahedral
E) trigonal planar
31) Of the following species, __________ will have bond angles of 120e .
A) NCl3
B) BCl3
C) PH3
D) ClF3
E) All of these will have bond angles of 120e.
32) The molecular geometry of the BrO3- ion is __________.
A) T-shaped
B) trigonal pyramidal
C) tetrahedral
D) bent
E) trigonal planar
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33) The molecular geometry of the left-most carbon atom in the molecule below is __________.
A) octahedral
B) tetrahedral
C) trigonal planar
D) T-shaped
E) trigonal bipyramidal
34) The bond angles marked a, b, and c in the molecule below are about __________, __________, and __________,
respectively.
A) 120e , 120e , 90 e
B) 90e, 90e, 90e
C) 120e , 120e , 109.5e
D) 109.5e, 90e, 120e
E) 109.5e , 120e , 109.5e
35) The central iodine atom in IF5 has __________ unbonded electron pairs and __________ bonded electron pairs
in its valence shell.
A) 1, 4
B) 4, 1
C) 1, 5
D) 0, 5
E) 5, 1
D) SF6
E) CH4
D) NF3
E) BF3
36) Of the molecules below, only __________ is polar.
A) SbF5
B) I2
C) AsH3
37) Of the molecules below, only __________ is nonpolar.
A) IF3
B) BrCl3
C) PBr3
38) The molecular geometry of the CHF3 molecule is __________, and the molecule is __________.
A) seesaw, nonpolar
B) trigonal pyramidal, polar
C) tetrahedral, nonpolar
D) seesaw, polar
E) tetrahedral, polar
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39) The electron-domain geometry of a carbon-centered compound is tetrahedral. The hybridization of the central
carbon atom is __________.
A) sp3
B) sp
C) sp3d2
D) sp2
E) sp3d
40) The hybridization of the carbon atom in carbon dioxide is __________.
A) sp3d
B) sp2
C) sp
D) sp3
E) sp3d2
41) The hybridization of the central atom in the XeF4 molecule is __________.
A) sp2
B) sp3d2
C) sp
D) sp3d
E) sp3
42) The sp3d2 atomic hybrid orbital set accommodates __________ electron domains.
A) 2
B) 3
C) 4
D) 5
E) 6
43) The hybridizations of iodine in IF3 and IF5 are __________ and __________, respectively.
A) sp3, sp3d
B) sp3d, sp3
C) sp3d, sp3d2
D) sp3d2, sp3d2
E) sp3d2, sp3d
44) The blending of one s atomic orbital and two p atomic orbitals produces __________.
A) two sp3 hybrid orbitals
B) three sp2 hybrid orbitals
C) two sp2 hybrid orbitals
D) three sp hybrid orbitals
E) three sp3 hybrid orbitals
45) The angles between sp2 orbitals are __________.
A) 109.5e
B) 120e
C) 180e
D) 45e
E) 90e
D) 13
E) 18
46) A typical triple bond consists of __________.
A) three ionic bonds
B) three pi bonds
C) three sigma bonds
D) two sigma and one pi bond
E) one sigma and two pi bonds
47) There is/are __________ s bond(s) in the molecule below.
A) 1
B) 2
C) 12
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48) There is/are __________ p bond(s) in the molecule below.
A) 0
B) 1
C) 2
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D) 4
E) 16
Answer Key
Testname: CH_08_09_PRAC_TEST.TST
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) C
ID: chem9b 9.1-3
2) D
ID: chem9b 9.1-4
3) B
ID: chem9b 9.1-9
4) E
ID: chem9b 9.1-11
5) B
ID: chem9b 9.1-12
6) B
ID: chem9b 9.1-29
7) B
ID: chem9b 9.1-38
8) D
ID: chem9b 9.1-45
9) B
ID: chem9b 9.1-52
10) B
ID: chem9b 9.1-61
11) D
ID: chem9b 9.1-64
12) A
ID: chem9b 9.1-65
13) E
ID: chem9b 9.1-68
14) A
ID: chem9b 9.1-72
15) D
ID: chem9b 9.1-79
16) C
ID: chem9b 9.1-85
17) B
ID: chem9b 9.1-86
18) E
ID: chem9b 9.1-87
19) E
ID: chem9b 9.1-88
20) C
ID: chem9b 9.1-94
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Answer Key
Testname: CH_08_09_PRAC_TEST.TST
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
21) (a)
DHrxn = D(C”O) + 2 D(H-H) - [3 D(C-H) + D(C-O) + D(O-H)]
3 D(C-H) = -DHrxn + D(C”O) + 2 D(H-H) - D(C-O) - D(O-H)
D(C-H) = (128 + 1072 + 2(436) - 358 - 463)/3 = 417
D(C-H) = 417 kJ/mol
(b) Tabulated values, like those in Table 8.4, are averaged from many bond energies measured for C-H bonds in many
different molecules.
ID: chem9b 9.1-105
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
22) C
ID: chem9b 9.1-109
23) D
ID: chem9b 9.1-111
24) E
ID: chem9b 10.1-3
25) E
ID: chem9b 10.1-4
26) C
ID: chem9b 10.1-7
27) B
ID: chem9b 10.1-9
28) A
ID: chem9b 10.1-10
29) E
ID: chem9b 10.1-11
30) B
ID: chem9b 10.1-16
31) B
ID: chem9b 10.1-26
32) B
ID: chem9b 10.1-27
33) B
ID: chem9b 10.1-28
34) E
ID: chem9b 10.1-30
35) C
ID: chem9b 10.1-34
36) C
ID: chem9b 10.1-45
37) E
ID: chem9b 10.1-48
38) E
ID: chem9b 10.1-55
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Answer Key
Testname: CH_08_09_PRAC_TEST.TST
39) A
ID: chem9b 10.1-60
40) C
ID: chem9b 10.1-64
41) B
ID: chem9b 10.1-65
42) E
ID: chem9b 10.1-68
43) C
ID: chem9b 10.1-71
44) B
ID: chem9b 10.1-86
45) B
ID: chem9b 10.1-88
46) E
ID: chem9b 10.1-101
47) C
ID: chem9b 10.1-106
48) C
ID: chem9b 10.1-107
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