Chemistry: The Central Science, 13e (Brown et al.)
Chapter 8 Basic Concepts of Chemical Bonding
8.1 Multiple-Choice Questions
1) Which of the following has eight valence electrons?
A) Ti4+
B) Kr
C) Cl–
D) Na+
E) all of the above
2) Which of the following does not have eight valence electrons?
A) Ca+
B) Rb+
C) Xe
D) Br–
E) All of the above have eight valence electrons.
3) Lattice energy is ________.
A) the energy required to convert a mole of ionic solid into its constituent ions in the gas phase
B) the energy given off when gaseous ions combine to form one mole of an ionic solid
C) the energy required to produce one mole of an ionic compound from its constituent elements in their
standard states
D) the sum of ionization energies of the components in an ionic solid
E) the sum of electron affinities of the components in an ionic solid
4) In ionic bond formation, the lattice energy of ions ________ as the magnitude of the ion charges
_______ and the radii ________.
A) increases, decrease, increase
B) increases, increase, increase
C) decreases, increase, increase
D) increases, increase, decrease
E) increases, decrease, decrease
5) Which energy change corresponds to the electron affinity of fluorine?
A) 2
B) 5
C) 4
D) 1
E) 6
6) Which energy change corresponds to the first ionization energy of potassium?
A) 2
B) 5
C) 4
D) 3
E) 6
7) Using the Born-Haber cycle, the ΔH°f of KBr is equal to ________.
A) ΔH°f [K (g)] + ΔH°f [Br (g)] + I1(K) + E(Br) + ΔHlattice
B) ΔH°f [K (g)] – ΔH°f [Br (g)] – I1(K) – E(Br) – ΔHlattice
C) ΔH°f [K (g)] – ΔH°f [Br (g)] + I1(K) – E(Br) + ΔHlattice
D) ΔH°f [K (g)] + ΔH°f [Br (g)] – I1 – E(Br) + ΔHlattice
E) ΔH°f [K (g)] + ΔH°f [Br (g)] + I1(K) + E(Br) – ΔHlattice
8) The type of compound that is most likely to contain a covalent bond is ________.
A) 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
B) a solid metal
C) one that is composed of only nonmetals
D) held together by the electrostatic forces between oppositely charged ions
E) There is no general rule to predict covalency in bonds.
9) In which of the molecules below is the carbon-carbon distance the shortest?
A) H2CCH2
B) H-C≡C-H
C) H3C—CH3
D) H2CCCH2
E) H3C—CH2—CH3
10) Of the molecules below, the bond in ________ is the most polar.
A) HBr
B) HI
C) HCl
D) HF
E) H2
11) Which of the following has the bonds correctly arranged in order of increasing polarity?
A) Be—F, Mg—F, N—F, O—F
B) O—F, N—F, Be—F, Mg—F
C) O—F, Be—F, Mg—F, N—F
D) N—F, Be—F, Mg—F, O—F
E) Mg—F, Be—F, N—F, O—F
12) The bond length in an HI molecule is 1.61 Å and the measured dipole moment is 0.44 D. What is the
magnitude (in units of e) of the negative charge on I in HI?
(1 debye = 3.34 × 10–30 coulomb-meters; e = 1.6 × 10–19 coulombs)
A) 1.6 × 10–19
B) 0.057
C) 9.1
D) 1
E) 0.22
13) The Lewis structure of N2H2 shows ________.
A) a nitrogen-nitrogen triple bond
B) a nitrogen-nitrogen single bond
C) each nitrogen has one nonbonding electron pair
D) each nitrogen has two nonbonding electron pairs
E) each hydrogen has one nonbonding electron pair
14) The Lewis structure of the CO32- ion is ________.
A)
B)
C)
D)
E)
15) In the nitrite ion (NO2–), ________.
A) both bonds are single bonds
B) both bonds are double bonds
C) one bond is a double bond and the other is a single bond
D) both bonds are the same
E) there are 20 valence electrons
16) Resonance structures differ by ________.
A) number and placement of electrons
B) number of electrons only
C) placement of atoms only
D) number of atoms only
E) placement of electrons only
17) The oxidation number of iron in Fe2O3 is ________.
A) -2
B) +1
C) +3
D) +2
E) -3
18) To convert from one resonance structure to another, ________.
A) only atoms can be moved
B) electrons and atoms can both be moved
C) only electrons can be moved
D) neither electrons nor atoms can be moved
E) electrons must be added
19) For resonance forms of a molecule or ion, ________.
A) one always corresponds to the observed structure
B) all the resonance structures are observed in various proportions
C) the observed structure is an average of the resonance forms
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
For the questions that follow, consider the BEST Lewis structures of the following oxyanions:
(i) NO2– (ii) NO3– (iii) SO32- (iv) SO42- (v) BrO3–
20) There can be four equivalent best resonance structures of ________.
A) (i)
B) (ii)
C) (iii)
D) (iv)
E) (v)
21) 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)
22) A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) NF3
B) IF3
C) PF3
D) SbF3
E) SO42-
23) Based on the octet rule, boron will most likely form a ________ ion.
A) B3-
B) B+
C) B3+
D) B2+
E) B2-
24) Which of the following does not have eight valence electrons?
A) Cl–
B) Xe
C) Ti+4
D) Rb+
E) Sr+
25) A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) PO43-
B) SiF4
C) CF4
D) SeF4
E) NF3
26) The central atom in ________ does not violate the octet rule.
A) SF4
B) KrF2
C) CF4
D) XeF4
E) ICl4–
27) A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) ClF3
B) PCl3
C) SO3
D) CCl4
E) CO2
28) A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) NI3
B) SO2
C) ICl5
D) SiF4
E) CO2
29) A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) NF3
B) BeH2
C) SO2
D) CF4
E) SO32-
30) Why don’t we draw double bonds between the Be atom and the Cl atoms in BeCl2?
A) That would give positive formal charges to the chlorine atoms and a negative formal charge to the
beryllium atom.
B) There aren’t enough electrons.
C) That would result in more than eight electrons around beryllium.
D) That would result in more than eight electrons around each chlorine atom.
E) That would result in the formal charges not adding up to zero.
31) Which atom can accommodate an octet of electrons, but doesn’t necessarily have to accommodate an
octet?
A) N
B) C
C) H
D) O
E) B
32) Bond enthalpy is ________.
A) always positive
B) always negative
C) sometimes positive, sometimes negative
D) always zero
E) unpredictable
33) 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) 1241
B) 689
C) -689
D) 1378
E) -1378
34) Of the bonds C-C, C C, and C≡C, the C–C bond is ________.
A) strongest/shortest
B) strongest/longest
C) weakest/longest
D) weakest/shortest
E) intermediate in both strength and length
35) Of the bonds C-N, C N, and C≡N, the C-N bond is ________.
A) strongest/shortest
B) strongest/longest
C) weakest/shortest
D) weakest/longest
E) intermediate in both strength and length
36) 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
37) Of the possible bonds between carbon atoms (single, double, and triple), ________.
A) a triple bond is longer than a single bond
B) a double bond is stronger than a triple bond
C) a single bond is stronger than a triple bond
D) a double bond is longer than a triple bond
E) a single bond is stronger than a double bond
38) Most explosives are compounds that decompose rapidly to produce ________ products and a great
deal of ________.
A) gaseous, gases
B) liquid, heat
C) soluble, heat
D) solid, gas
E) gaseous, heat
39) Dynamite consists of nitroglycerine mixed with ________.
A) potassium nitrate
B) damp KOH
C) TNT
D) diatomaceous earth or cellulose
E) solid carbon
40) Dynamite ________.
A) was invented by Alfred Nobel
B) is made of nitroglycerine and an absorbent such as diatomaceous earth
C) is a much safer explosive than pure nitroglycerine
D) is an explosive
E) all of the above
8.2 Bimodal Questions
1) Based on the octet rule, magnesium most likely forms a ________ ion.
A) Mg2+
B) Mg2-
C) Mg6-
D) Mg6+
E) Mg–
2) Based on the octet rule, phosphorus most likely forms a ________ ion.
A) P3+
B) P3-
C) P5+
D) P5-
E) P+
3) Based on the octet rule, aluminum most likely forms an ________ ion.
A) Al3+
B) Al4+
C) Al4-
D) Al+
E) Al–
4) Based on the octet rule, iodine most likely forms an ________ ion.
A) I2+
B) I4+
C) I4-
D) I+
E) I–
5) The electron configuration of the phosphide ion (P3-) is ________.
A) [Ne]3s2
B) [Ne]3s23p1
C) [Ne]3s23p3
D) [Ne]3p2
E) [Ne]3s23p6
6) The electron configuration of the sulfide ion (S2-) is ________.
A) [Ne]3s2
B) [Ne]3s23p1
C) [Ne]3s23p4
D) [Ne]3p2
E) [Ne]3s23p6
7) The halogens, alkali metals, and alkaline earth metals have ________ valence electrons, respectively.
A) 7, 4, and 6
B) 1, 5, and 7
C) 8, 2, and 3
D) 7, 1, and 2
E) 2, 7, and 4
8) The only noble gas without eight valence electrons is ________.
A) Ar
B) Ne
C) He
D) Kr
E) All noble gases have eight valence electrons.
9) Which of the following would have to lose two electrons in order to achieve a noble gas electron
configuration?
O Sr Na Se Br
A) O, Se
B) Sr
C) Na
D) Br
E) Sr, O, Se
10) Which of the following would have to lose three electrons in order to achieve a noble gas electron
configuration?
Si Mg Al Cl P
A) Si, P
B) Al
C) P
D) Cl
E) Mg, Al, P
11) Which of the following would have to gain two electrons in order to achieve a noble gas electron
configuration?
O Sr Na Se Br
A) Br
B) Sr
C) Na
D) O, Se
E) Sr, O, Se
12) For a given arrangement of ions, the lattice energy increases as ionic radius ________ and as ionic
charge ________.
A) decreases, increases
B) increases, decreases
C) increases, increases
D) decreases, decreases
E) This cannot be predicted.
13) For a given arrangement of ions, the lattice energy decreases as ionic radius ________ and as ionic
charge ________.
A) decreases, increases
B) increases, decreases
C) increases, increases
D) decreases, decreases
E) This cannot be predicted.
14) The electron configuration of the S2– ion is ________.
A) [Ar]3s23p6
B) [Ar]3s23p2
C) [Ne]3s23p2
D) [Ne]3s23p6
E) [Kr]3s22p6
15) The electron configuration of the P3- ion is ________.
A) [Ar]3s23p6
B) [Ar]3s23p2
C) [Ne]3s23p6
D) [Ne]3s23p2
E) [Kr]3s22p6
16) What species has the electron configuration [Ar]3d2?
A) Mn2+
B) Cr2+
C) V3+
D) Fe3+
E) K+
17) What species has the electron configuration [Ar]3d4?
A) Mn2+
B) Cr2+
C) V3+
D) Fe3+
E) K+
18) What is the electron configuration for the Co2+ ion?
A) [Ar]4s13d6
B) [Ar]3d7
C) [Ar]3d5
D) [Ar]4s23d9
E) [Ne]3s23p10
19) What is the electron configuration for the Fe3+ ion?
A) [Ar]4s13d6
B) [Ar]4s03d7
C) [Ar]4s03d5
D) [Ar]4s23d9
E) [Ne]3s23p10
20) What is the electron configuration for the Fe2+ ion?
A) [Ar]4s03d6
B) [Ar]4s23d4
C) [Ar]4s03d8
D) [Ar]4s23d8
E) [Ar]4s63d2
21) The formula of palladium (IV) sulfide is ________.
A) Pd2S4
B) PdS4
C) Pd4S
D) PdS2
E) Pd2S2
22) Elements from opposite sides of the periodic table tend to form ________.
A) covalent compounds
B) ionic compounds
C) compounds that are gaseous at room temperature
D) homonuclear diatomic compounds
E) covalent compounds that are gaseous at room temperature
23) Determining lattice energy from Born-Haber cycle data requires the use of ________.
A) the octet rule
B) Coulomb’s law
C) Periodic law
D) Hess’s law
E) Avogadro’s number
24) A ________ covalent bond between the same two atoms is the longest.
A) single
B) double
C) triple
D) strong
E) They are all the same length.
25) How many hydrogen atoms must bond to silicon to give it an octet of valence electrons?
A) 1
B) 2
C) 3
D) 4
E) 5
26) A double bond consists of ________ pairs of electrons shared between two atoms.
A) 1
B) 2
C) 3
D) 4
E) 6
27) A triple bond consists of ________ pairs of electrons shared between two atoms.
A) 1
B) 2
C) 3
D) 4
E) 6
28) What is the maximum number of double bonds that a hydrogen atom can form?
A) 0
B) 1
C) 2
D) 3
E) 4
29) What is the maximum number of double bonds that a carbon atom can form?
A) 4
B) 1
C) 0
D) 2
E) 3
30) What is the maximum number of triple bonds that a carbon atom can form?
A) 4
B) 1
C) 0
D) 2
E) 3
31) In the molecule below, which atom has the largest partial negative charge?
Cl
∣
F— C —Br
∣
I
A) Cl
B) F
C) Br
D) I
E) C
32) The ability of an atom in a molecule to attract electrons is best quantified by the ________.
A) paramagnetism
B) diamagnetism
C) electronegativity
D) electron charge–to-mass ratio
E) first ionization potential