31) Which group 3A element exhibits the most nonmetallic character?
A) B
B) Tl
C) Pb
D) Sb
32) Which elements of group 3A are commonly used in semiconductors?
A) Tl and Al
B) Tl and Ga
C) Ga and In
D) In and Tl
33) Which group 3A element has the highest electronegativity?
A) B
B) Al
C) Ga
D) Si
34) What is the geometric structure of BF3 and the hybridization of the B atom?
A) trigonal planar and sp2 hybridization
B) trigonal planar and sp3 hybridization
C) pyramidal and sp
hybridization
D) tetrahedral and sp2 hybridization
35) Which of the following is not a use of aluminum?
A) soda cans
B) cooking pots
C) cooking utensils
D) plastic bottles
36) Which element of group 4A is the most abundant in the earth’s crust?
A) C
B) Si
C) Sn
D) N
37) Which of the following chlorides is the most ionic?
A) CH2Cl2
B) SiCl4
C) PbCl2
D) PbCl4
38) Which carbon containing compound is an inorganic compound?
A) C7H7NO2
B) HCN
C) CH3CO2H
D) C6H5Br
39) Which compound has carbon with a negative oxidation number?
A) CO2
B) CaC2
C) HCN
D) Li2CO3
40) What is the oxidation number of carbon in CaC2?
A) +4
B) 0
C) -1
D) -2
41) Approximately 90% of the Earth’s crust is composed of what type of compounds?
A) carbonates
B) oxides
C) silicates
D) sulfates
42) What is the basic building block of all silicates?
A) Si2O64-
B) Si
C) SiO2
D) SiO44-
43) What is the range of oxidation states that are exhibited by P?
A) from -3 to 0
B) from -2 to +2
C) from -3 to +5
D) from -1 to +5
44) What is the most stable oxidation state for Bi in bismuth compounds?
A) -2
B) +1
C) +3
D) +2
45) Which one of the following compounds that contains a Group 5A element is least likely to exist?
A) NF3
B) NBr5
C) PF3
D) PI5
46) In which compound is phosphorus in its lowest oxidation state?
A) P2O5
B) PBr3
C) PH3
D) PCl5
47) Which one of the following elements forms the most acidic binary oxide?
A) K
B) Si
C) P
D) As
48) Which one of the following compounds that contains a Group 5A element is least likely to exist?
A) NBr3
B) NBr5
C) PBr3
D) PBr5
49) What are the basic oxides of the following set Cs2O, CaO, P4O10, SO3, and I2O7?
A) Cs2O and CaO
B) Cs2O, CaO, and P4O10
C) P4O10, SO3, and I2O7
D) SO3 and I2O7
50) Which one of the following elements forms the most acidic binary oxide?
A) Ne
B) Cu
C) N
D) Li
51) Which group 6A element has the most negative electron affinity?
A) Te
B) S
C) N
D) C
52) Which group 6A element is naturally radioactive?
A) S
B) U
C) Dy
D) Po
53) Which element of group 6A has the highest melting point?
A) Ge
B) As
C) Po
D) Se
54) Which element of group 6A has the highest boiling point?
A) Al
B) O
C) Po
D) As
55) Which is classified as an ionic binary oxide?
A) BaO
B) CO2
C) N2O5
D) SO3
56) Which is classified as an amphoteric binary oxide?
A) B2O3
B) CO2
C) Ga2O3
D) Rb2O
57) Which one of the following binary oxides is the most acidic?
A) K2O
B) Ga2O3
C) BeO
D) Cl2O7
58) Which one of the following binary oxides is the most covalent?
A) Li2O
B) BaO
C) SiO2
D) Br2O5
59) Which one of the following binary oxides is the most basic?
A) Na2O
B) PbO2
C) I2O5
D) TeO3
60) What statement is not representative of the chemistry of H2S?
A) It has a tetrahedral geometry.
B) It is an extremely toxic substance.
C) It is a weak diprotic acid.
D) It is a weak reducing agent.
22.3 Short Answer Questions
1) Main-group elements are those elements in groups ________ through ________ of the periodic table.
2) The number of metallic elements in period 3 of the periodic table is ________.
3) Elements in period 2 of the periodic table differ markedly from the heavier elements in the same group
due to their especially small ________ and high ________.
4) The product of the reaction of lithium with nitrogen is ________.
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5) Lithium reacts with oxygen to form an oxide with the formula ________.
6) The oxidation number of the oxygen atoms in CaO2 is ________.
7) Elements in group 3A of the periodic table have the valence electron configuration ________.
8) The B—H—B bond in B2H6 is a three-________, two-________ bond.
9) In the mixed aluminum-boron hydride AlBH6, the number of hydrogen involved in 2c-2e bonds is
________, and the number of hydrogen involved in 3c-2e bonds is ________.
10) The number of semimetals in group 4A of the periodic table is ________.
11) Carbon combines with some metals and semimetals to form carbides. What is the formula of
aluminum carbide?
12) The percentage of carbon in the endohedral fullerene complexes KrC60 and XeC60 is ________%C and
________%C, respectively.
13) Fullerene is an ________ of carbon.
14) When a person exhales through a straw into water, the water will have a(n) ________ pH due to the
reaction ________.
15) The charge, n, on the cyclic anion Si6O18n that is found in the mineral beryl is ________.
16) The ratio of oxygen atoms to silicon atoms in orthosilicate, single-strand silicates, double-strand
silicates, and cyclic silicates is ________, ________, ________, and ________, respectively.
17) Wollastonite, CaSiO3, is an example of a(n) ________ silicate.
18) Diopside, CaMgSi2O6, is an example of a(n) ________ (orthosilicate, single–strand silicate, double–
strand silicate, and cyclic silicate).
19) The most acidic oxides of the group 5A elements are oxides of the element ________.
20) The oxidation numbers of nitrogen in NH4NO3 are ________ and ________.
21) In the reaction below, ________ is the oxidizing agent and ________ is the reducing agent.
N2H4(l) + N2O4(l) → 3 N2(g) + 4 H2O(g)
22) When P4O10 is dissolved in water, the water will have a(n) ________ pH due to the reaction ________.
23) Why is H3PO4 a weak triprotic acid whereas H3PO3 is a weak diprotic acid?
24) Ring strain the cause of high molecular reactivity that occurs when the angles in a ring of atoms are
not close to “normal”bond angles (90° when the bonds are formed by atoms using pure p-orbitals, 109.5°
using sp3 hybrid orbitals, 120° using sp2 orbitals, etc.). The angles in white phosphorus, P4, measure
________, and P4 ________ expected to exhibit ring strain and be very reactive.
25) Adenosine triphosphate (ATP) plays an important role in energy transfer within cells. ATP can be
considered to be an ester of triphosphoric acid, which is formed by the combination of three phosphoric
acid molecules with the elimination of two water molecules. What is the formula of triphosphoric acid?
26) The oxidation number of sulfur in S
O2
is ________.
27) Binary oxides can be classified as acidic, amphoteric, or basic. MgO, Al2O3, and SO3 are classified as
________, ________, and ________ oxides, respectively.
28) Of Na2O, SO2, and SO3, equimolar aqueous solutions of ________ would be most acidic and of
________ would be most basic.
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29) The most stable allotrope of sulfur is S8. What are the approximate bond angles in S8?
30) Disproportionation is a reaction in which a reactant is both oxidized and reduced in the same
reaction. In the disproportionation reaction below, the oxidation number of chlorine in Cl2, ClO–, and Cl–
is ________, ________, and ________, respectively.
Cl2(g) + 2 OH–(aq) → ClO–(aq) + Cl–(aq) + H2O(l)
31) If niobium loses all of its valence electrons when it reacts with fluorine, what is the formula of the
neutral binary compound that results?
32) When the equation for the reaction of KBr(aq) with MnO2(s) to produce Br2 and Mn2+(aq) in acidic
solution is balanced, the coefficient in front of the Br2 is ________.