CHE 1401 - Fall 2016 - Chapter 8
Homework 8 (Chapter 8: Basic concepts of chemical bonding)
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MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the
question.
1) Which of the following names is/are correct for the compound TiO2?
1)
A) titanium dioxide and titanium (IV) oxide
B) titanium oxide and titanium (IV) dioxide
C) titanium oxide
D) titanium (IV) dioxide
E) titanium (II) oxide
2) Resonance structures differ by __________.
A) number of electrons only
B) number of atoms only
C) placement of electrons only
D) number and placement of electrons
E) placement of atoms only
2)
3) Of the molecules below, the bond in __________ is the most polar.
A) HBr
B) HI
C) HCl
D) H2
3)
E) HF
4) A valid Lewis structure of __________ cannot be drawn without violating the
octet rule.
A) ICl5
B) SO2
C) SiF4
D) NI3
E) CO 2
4)
5) The type of compound that is most likely to contain a covalent bond is
__________.
A) held together by the electrostatic forces between oppositely charged ions
B) one that is composed of a metal from the far left of the periodic table and a
nonmetal from the far right of the periodic table
C) a solid metal
D) one that is composed of only nonmetals
E) There is no general rule to predict covalency in bonds.
5)
6) Which of the following has eight valence electrons?
A) Na+
6)
B) Ti4+
C) ClD) Kr
E) all of the above
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7) The electron configuration [Kr]4d10 represents __________.
A) Sn+2
B) Sr+2
C) Ag+1
D) Rb+1
7)
E) Te+2
8) 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
8)
9) For resonance forms of a molecule or ion, __________.
A) all the resonance structures are observed in various proportions
B) the observed structure is an average of the resonance forms
C) one always corresponds to the observed structure
D) the same atoms need not be bonded to each other in all resonance forms
E) there cannot be more than two resonance structures for a given species
9)
10) In the nitrite ion (NO2-), __________.
A) both bonds are the same
B) there are 20 valence electrons
C) both bonds are double bonds
D) both bonds are single bonds
E) one bond is a double bond and the other is a single bond
10)
11) A valid Lewis structure of __________ cannot be drawn without violating the
octet rule.
A) SiF4
B) NF3
C) PO43D) CF4
E) SeF4
11)
12) Why don't we draw double bonds between the Be atom and the Cl atoms
in BeCl2?
A) That would result in more than eight electrons around beryllium.
B) There aren't enough electrons.
C) That would give positive formal charges to the chlorine atoms and a
negative formal charge to the beryllium atom.
D) That would result in the formal charges not adding up to zero.
E) That would result in more than eight electrons around each chlorine atom.
12)
2
13) The Lewis structure of the CO32- ion is __________.
A)
13)
B)
C)
D)
E)
14) Based on the octet rule, boron will most likely form a __________ ion.
A) B3B) B2+
C) B1+
D) B2E) B3+
3
14)
15) Of the atoms below, __________ is the least electronegative.
A) Rb
B) Si
C) Ca
D) Cl
15)
E) F
16) In the Lewis symbol for a sulfur atom, there are __________ paired and
__________ unpaired electrons.
A) 2, 4
B) 5, 1
C) 4, 2
D) 2, 2
E) 0, 6
16)
17) Which of the following has the bonds correctly arranged in order of increasing
polarity?
A) NF, BeF, MgF, OF
B) OF, BeF, MgF, NF
C) BeF, MgF, NF, OF
D) MgF, BeF, NF, OF
E) OF, NF, BeF, MgF
17)
18) Most explosives are compounds that decompose rapidly to produce __________
products and a great deal of __________.
A) gaseous, heat
B) solid, gas
C) gaseous, gases
D) soluble, heat
E) liquid, heat
18)
For the questions that follow, consider the BEST Lewis structures of the following oxyanions:
(i) NO2- (ii) NO3- (iii) SO32- (iv)SO42- (v) BrO319) There can be four equivalent best resonance structures of __________.
A) (i)
B) (ii)
C) (iii)
D) (iv)
E) (v)
19)
20) In which of the ions do all X-O bonds (X indicates the central atom) have the
same length?
A) none
B) all
C) (i) and (ii)
D) (iii) and (v)
E) (iii), (iv), and (v)
20)
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21) The Lewis structure of N2H2 shows __________.
21)
A) a nitrogen-nitrogen triple bond
B) a nitrogen-nitrogen single bond
C) each hydrogen has one nonbonding electron pair
D) each nitrogen has one nonbonding electron pair
E) each nitrogen has two nonbonding electron pairs
22) In ionic bond formation, the lattice energy of ions ________ as the magnitude of
the ion charges _______ and the radii __________.
A) decreases, increase, increase
B) increases, decrease, decrease
C) increases, increase, decrease
D) increases, decrease, increase
E) increases, increase, increase
22)
23) A valid Lewis structure of __________ cannot be drawn without violating the
octet rule.
A) CF4
B) SO32C) NF3
D) BeH2
E) SO2
23)
24) Of the possible bonds between carbon atoms (single, double, and triple),
__________.
A) a single bond is stronger than a double bond
B) a triple bond is longer than a single bond
C) a single bond is stronger than a triple bond
D) a double bond is longer than a triple bond
E) a double bond is stronger than a triple bond
24)
25) The central atom in __________ does not violate the octet rule.
A) XeF4
B) KrF2
C) CF4
D) SF4
25)
E) ICl4-
26) Bond enthalpy is __________.
A) sometimes positive, sometimes negative
B) always negative
C) always positive
D) always zero
E) unpredictable
26)
27) Of the following, __________ cannot accommodate more than an octet of
electrons.
A) P
B) As
C) O
D) I
E) S
27)
28) Of the atoms below, __________ is the most electronegative.
A) O
B) N
C) Cl
D) F
28)
5
E) Br
29) Which two bonds are most similar in polarity?
A) AlCl and IBr
B) ClCl and BeCl
C) BF and ClF
D) OF and ClF
E) IBr and SiCl
29)
30) Which atom can accommodate an octet of electrons, but doesn't necessarily
have to accommodate an octet?
A) H
B) N
C) B
D) O
E) C
30)
31) Dynamite consists of nitroglycerine mixed with __________.
A) solid carbon
B) potassium nitrate
C) damp KOH
D) TNT
E) diatomaceous earth or cellulose
31)
32) Given that the average bond energies for C-H and C-Br bonds are 413 and 276
kJ/mol, respectively, the heat of atomization of bromoform (CHBr3) is
__________ kJ/mol.
A) -1378
B) -689
C) 1378
D) 689
E) 1241
32)
33) Of the bonds below, __________ is the least polar.
A) C, F
B) Si, Cl
C) Na, S
D) P, S
33)
E) Na, Cl
34) A valid Lewis structure of __________ cannot be drawn without violating the
octet rule.
A) PCl3
B) CO2
C) ClF3
D) CCl4
E) SO3
34)
35) The oxidation number of phosphorus in PF3 is __________.
A) +3
B) +1
C) +2
D) -2
35)
36) Which of the following does not have eight valence electrons?
A) ClB) Rb+1
C) Ti+4
D) Sr+1
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E) -3
36)
E) Xe
37) Using the Born-Haber cycle, the ΔHf° of KBr is equal to __________.
A) ΔHf°[K (g)] + ΔHf°[Br (g)]
B) ΔHf°[K (g)] - ΔHf°[Br (g)]
C) ΔHf°[K (g)] - ΔHf°[Br (g)]
D) ΔHf°[K (g)] + ΔHf°[Br (g)]
37)
- I1 - E(Br) + ΔHlattice
- I1(K) - E(Br) - ΔHlattice
+ I1(K) - E(Br) + ΔHlattice
+ I1(K) + E(Br) - ΔHlattice
E) ΔHf°[K (g)] + ΔHf°[Br (g)] + I1(K) + E(Br) + ΔHlattice
38) Of the ions below, only __________ has a noble gas electron configuration.
A) I+
B) O2+
C) S3D) KE) Cl-
38)
39) The chloride of which of the following metals should have the greatest lattice
energy?
A) rubidium
B) potassium
C) cesium
D) lithium
E) sodium
39)
40) Which of the following names is/are correct for the compound SnCl4?
A) tin tetrachloride and tin (IV) chloride
B) tin (IV) tetrachloride
C) tin chloride
D) tin chloride and tin (II) tetrachloride
E) tin (II) chloride and tin (IV) chloride
40)
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