Chemistry: A Molecular Approach (Tro)
Chapter 8 Periodic Properties of the Elements
1) Give the ground state electron configuration for Se.
A) [Ar]4s23d104p4
B) [Ar]4s24d104p4
C) [Ar]4s23d104p6
D) [Ar]4s23d10
E) [Ar]3d104p4
Answer: A
2) Give the ground state electron configuration for I.
A) [Kr]5s24d105p6
B) [Kr]5s24d105p5
C) [Kr]4d105p6
D) [Kr]5s25p6
E) [Kr]5s25d105p6
Answer: B
3) Give the ground state electron configuration for Sr.
A) [Kr]5s24d2
B) [Kr]5s24d105p2
C) [Kr]5s2
D) [Kr]5s25d105p2
E) [Kr]5s24d10
Answer: C
4) Give the ground state electron configuration for Pb.
A) [Xe]6s26p2
B) [Xe]6s25d106p2
C) [Xe]6s25f146d106p2
D) [Xe]6s24f145d106p2
E) [Xe]6s25f145d106p2
Answer: D
5) Give the ground state electron configuration for Cd.
A) [Kr]5s25d10
B) [Kr]5s24d105p2
C) [Kr]4d10
D) [Kr]5s24d8
E) [Kr]5s24d10
Answer: E
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6) Give the ground state electron configuration for Br ⁻ .
A) [Ar]4s23d104p6
B) [Ar]4s23d104p5
C) [Ar]4s24p6
D) [Ar]4s24d104p6
E) [Ar]4s23d104p4
Answer: A
7) Give the ground state electron configuration for Mg2 ⁺ .
A) 1s22s22p63s2
B) 1s22s22p6
C) 1s22s22p63s23p2
D) 1s22s22p63s23p6
E) 1s22s22p63s1
Answer: B
8) Give the ground state electron configuration for Rb ⁺ .
A) [Ar]4s24p6
B) [Kr]5s1
C) [Ar]4s23d104p6
D) [Kr]5s2
E) [Kr]5s24d2
Answer: C
9) Give the ground state electron configuration for Se2 ⁻ .
A) [Ar]4s23d104p4
B) [Ar]4s23d104p2
C) [Ar]4s24p6
D) [Ar]4s23d104p6
E) [Ar]4s23d84p6
Answer: D
10) Give the ground state electron configuration for the ion of Ba.
A) [Kr]5s25p6
B) [Kr]5s24d105p66s26p2
C) [Kr]5s24d105p66s1
D) [Kr]5s24d105p66s2
E) [Kr]5s24d105p6
Answer: E
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11) Choose the orbital diagram that represents the ground state of N.
A)
B)
C)
D)
E)
Answer: A
12) Choose the valence orbital diagram that represents the ground state of Zn.
A)
B)
C)
D)
E)
Answer: A
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13) Choose the valence orbital diagram that represents the ground state of Sr2 ⁺
.
A)
B)
C)
D)
E)
Answer: D
14) Choose the valence orbital diagram that represents the ground state of Se2 ⁻ .
A)
B)
C)
D)
E)
Answer: E
15) Write out the orbital diagram that represents the ground state of As. How many unpaired electrons are there?
A) 0
B) 4
C) 3
D) 2
E) 1
Answer: C
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16) Choose the ground state electron configuration for Ti2 ⁺ .
A) [Ar]3d2
B) [Ar]4s2
C) [Ar]4s23d2
D) [Ar]4s23d4
E) [Ar]3d4
Answer: A
17) Choose the ground state electron configuration for Zn2 ⁺ .
A) [Ar]4s23d8
B) [Ar]3d10
C) [Ar]4s23d6
D) [Ar]
E) [Ar]3d8
Answer: B
18) Choose the ground state electron configuration for Zr2 ⁺ .
A) [Kr]5s2
B) [Kr]5s24d2
C) [Kr]4d2
D) [Kr]
E) [Kr]5s24d4
Answer: C
19) Choose the ground state electron configuration for Cr3 ⁺ .
A) [Ar]4s13d2
B) [Ar]
C) [Ar]4s23d6
D) [Ar]3d3
E) [Ar]4s23d1
Answer: D
20) Choose the paramagnetic species from below.
A) Ca
B) O2 ⁻
C) Cd2 ⁺
D) Zn
E) Nb3 ⁺
Answer: E
21) Choose the diamagnetic species from below.
A) Sn2 ⁺
B) Br
C) P
D) Cr
E) None of the above are diamagnetic.
Answer: A
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22) Choose the paramagnetic species from below.
A) Ti4 ⁺
B) O
C) Ar
D) All of the above are paramagnetic.
E) None of the above are paramagnetic.
Answer: B
23) How many of the following species are paramagnetic?
Sc3 ⁺ Br ⁻ Mg2
⁺
Se
A) 0
B) 2
C) 1
D) 4
E) 3
Answer: C
24) How many of the following species are diamagnetic?
Cs Zr2 ⁺ Al3 ⁺ Hg2 ⁺
A) 1
B) 3
C) 0
D) 2
E) 4
Answer: D
25) Give the set of four quantum numbers that represent the last electron added (using the Aufbau principle) to the Cl atom.
A) n = 3, l = 1, ml = 1, ms = +
1
2
B) n = 3, l = 0, ml = 0, ms = -
1
2
C) n = 3, l = 1, ml = 0 , ms = +
1
2
D) n = 2, l = 1, ml = 0, ms = -
1
2
E) n = 3, l = 1 , ml = 0, ms = -
1
2
Answer: E
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26) Give the set of four quantum numbers that represent the last electron added (using the Aufbau principle) to the Sr atom.
A) n = 5, l = 0, ml = 0, ms = -
1
2
B) n = 4, l = 1, ml = 1, ms = -
1
2
C) n = 5, l = 1, ml = 0, ms = +
1
2
D) n = 4, l = 1, ml = 1, ms = +
1
2
E) n = 5, l = 1, ml = 1 , ms = -
1
2
Answer: A
27) Give the set of four quantum numbers that represent the last electron added (using the Aufbau principle) to the Zn atom.
A) n = 4, l = 3, ml = 3, ms = -
1
2
B) n = 3, l = 2, ml = 2, ms = -
1
2
C) n = 3, l = 1, ml = 1, ms = +
1
2
D) n = 3, l = 3, ml = 2, ms = -
1
2
E) n = 3, l = 2, ml = 0, ms = +
1
2
Answer: B
28) Give the set of four quantum numbers that represent the electron gained to form the Br ION from the Br atom.
A) n = 4, l = 2, ml = 1, ms = -
1
2
B) n = 4, l = 0, ml = 1, ms = +
1
2
C) n = 4, l = 1, ml = 1, ms = -
1
2
D) n = 3, l = 2, ml = 2, ms = +
1
2
E) n = 4, l = 1, ml =1 , ms = +
1
2
Answer: C
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29) Give the set of four quantum numbers that represent the electron lost to form the K ION from the K atom.
A) n = 3, l = 1, ml = 1, ms = -
1
2
B) n = 4, l = 1, ml = 1, ms = +
1
2
C) n = 4, l = 4, ml = 0, ms = -
1
2
D) n = 4, l = 0, ml = 0, ms = +
1
2
E) n = 3, l = 0, ml = 1, ms = +
1
2
Answer: D
30) Give the set of four quantum numbers that represent the electron lost to form the Rb ION from the Rb atom.
A) n = 5, l = 0, ml = 0, ms = -
1
2
B) n = 4, l = 1, ml = 1, ms = -
1
2
C) n = 5, l = 1, ml = 0, ms = +
1
2
D) n = 4, l = 1, ml = 0, ms = -
1
2
E) n = 5, l = 0, ml = 0, ms = +
1
2
Answer: E
31) Which of the following statements is TRUE?
A) An orbital that penetrates into the region occupied by core electrons is less shielded from nuclear charge than an orbital that does not penetrate and therefore has a lower energy.
B) An orbital that penetrates into the region occupied by core electrons is more shielded from nuclear charge than an orbital that does not penetrate and therefore has a lower energy.
C) It is possible for two electrons in the same atom to have identical values for all four quantum numbers.
D) Two electrons in the same orbital can have the same spin.
E) None of the above are true.
Answer: A
32) How many unpaired electrons are present in the ground state P atom?
A) 0
B) 3
C) 1
D) 2
E) 4
Answer: B
33) How many unpaired electrons are present in the ground state Kr atom?
A) 1
B) 2
C) 0
D) 3
E) 5
Answer: C
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34) How many unpaired electrons are present in the ground state Ge atom?
A) 0
B) 3
C) 1
D) 2
E) 4
Answer: D
35) How many valence electrons does an atom of S have?
A) 3
B) 1
C) 2
D) 4
E) 6
Answer: E
36) How many valence electrons does an atom of Ba possess?
A) 2
B) 1
C) 8
D) 6
E) 3
Answer: A
37) How many valence electrons does an atom of Ti possess?
A) 2
B) 4
C) 6
D) 8
E) 0
Answer: B
38) How many valence electrons does an atom of Cu possess?
A) 2
B) 9
C) 11
D) 3
E) 1
Answer: C
39) How many valence electrons does an atom of Al possess?
A) 1
B) 2
C) 5
D) 3
E) 8
Answer: D
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40) How many valence electrons do the halogens possess?
A) 5
B) 6
C) 2
D) 1
E) 7
Answer: E
41) How many valence electrons do the alkali metals possess?
A) 1
B) 2
C) 7
D) 6
E) 8
Answer: A
42) Choose the statement that is TRUE.
A) Outer electrons efficiently shield one another from nuclear charge.
B) Core electrons efficiently shield outer electrons from nuclear charge.
C) Valence electrons are most difficult of all electrons to remove.
D) Core electrons are the easiest of all electrons to remove.
E) All of the above are true.
Answer: B
43) Place the following elements in order of increasing atomic radius.
P Ba Cl
A) Ba < P < Cl
B) P < Cl < Ba
C) Cl < P < Ba
D) Cl < Ba < P
E) Ba < Cl < P
Answer: C
44) Place the following elements in order of decreasing atomic radius.
Xe Rb Ar
A) Ar > Xe > Rb
B) Xe > Rb > Ar
C) Ar > Rb > Xe
D) Rb > Xe > Ar
E) Rb > Ar > Xe
Answer: D
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45) Place the following in order of increasing atomic radius.
As O Br
A) As < Br < O
B) O < As < Br
C) Br < As < O
D) As < O < Br
E) O < Br < As
Answer: E
46) Place the following in order of increasing radius.
Ca2 ⁺
A) Ca2 ⁺ < Cl ⁻
S2 ⁻
< S2 ⁻
Cl ⁻
B) Cl ⁻ < Ca2 ⁺ < S2 ⁻
C) S2 ⁻
< Cl ⁻
< Ca2 ⁺
D) Ca2 ⁺ < S2 ⁻< Cl ⁻
E) Cl ⁻ < S2 ⁻ < Ca2 ⁺
Answer: A
47) Place the following in order of increasing radius.
Br ⁻ Na ⁺ Rb ⁺
A) Br ⁻ < Rb ⁺ <
B) Na ⁺ < Rb ⁺ < Br ⁻
Na ⁺
C) Rb ⁺ < Br ⁻ < Na ⁺
D) Br ⁻ < Na ⁺ < Rb ⁺
E) Rb ⁺ < Na ⁺ < Br ⁻
Answer: B
48) Place the following in order of decreasing radius.
Te2 ⁻ F ⁻
A) F ⁻ > O2 ⁻ > Te2 ⁻
B) F ⁻ > Te2 ⁻ > O2 ⁻
C) Te2 ⁻ > O2 ⁻ > F ⁻
D) Te2 ⁻
> F ⁻
> O2 ⁻
E) O2 ⁻ > F ⁻ > Te2 ⁻
Answer: C
O2 ⁻
49) Which reaction below represents the first ionization of O?
A) O ⁺ (g) + e ⁻ → O(g)
B) O(g) + e ⁻ → O ⁻ (g)
C) O ⁻ (g) → O(g) + e ⁻
D) O(g) → O ⁺ (g) + e ⁻
E) O ⁻ (g) + e ⁻ → O2 ⁻ (g)
Answer: D
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50) Which reaction below represents the second ionization of Sr?
A) Sr(g) → Sr ⁺ (g) + e ⁻
B) Sr2 ⁺ (g) + e ⁻ → Sr ⁺ (g)
C) Sr ⁺ (g) + e ⁻ → Sr(g)
D) Sr ⁻
(g) + e ⁻ → Sr2 ⁻ (g)
E) Sr ⁺ (g) → Sr2 ⁺ (g) + e ⁻
Answer: E
51) What period 3 element is described by the following ionization energies (all in kJ/mol)?
IE1 = 1012 IE2 = 1900 IE3 = 2910 IE4 = 4960 IE5 = 6270 IE6 = 22,200
A) Si
B) S
C) P
D) Cl
E) Mg
Answer: C
52) Which reaction below represents the electron affinity of Li?
A) Li(g) + e ⁻ → Li ⁻ (g)
B) Li(g) → Li ⁺ (g) + e ⁻
C) Li(g) + e ⁻ → Li ⁺ (g)
D) Li ⁺ (g) → Li(g) + e ⁻
E) Li ⁺ (g) + e ⁻ → Li(g)
Answer: A
53) Which reaction below represents the second electron affinity of S?
A) S(g) + e ⁻ → S ⁻ (g)
B) S ⁻ (g) + e ⁻ → S2 ⁻ (g)
C) S(g) → S ⁺ (g) + e ⁻
D) S ⁻ (g) → S(g) + e ⁻
E) S2 ⁻ (g) → S ⁻ (g) + e ⁻
Answer: B
54) Place the following in order of increasing IE1.
N F As
A) N < As < F
B) As < N < F
C) F < N < As
D) As < F < N
E) F < N < As
Answer: B
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55) Place the following in order of decreasing IE1.
Cs Mg Ar
A) Cs > Mg > Ar
B) Mg > Ar > Cs
C) Ar > Mg > Cs
D) Cs > Ar > Mg
E) Mg > Cs > Ar
Answer: C
56) Place the following in order of increasing IE1.
K Ca Rb
A) Ca < K < Rb
B) Rb < Ca < K
C) Ca < Rb < K
D) Rb < K < Ca
E) K < Ca < Rb
Answer: D
57) Place the following in order of decreasing metallic character.
P As K
A) P > As > K
B) As > P > K
C) K > P > As
D) As > K > P
E) K > As > P
Answer: E
58) Place the following in order of increasing metallic character.
Br Cs Se
A) Br < Se < Cs
B) Se < Br < Cs
C) Cs < Br < Se
D) Cs < Se < Br
E) Br < Cs < Se
Answer: A
59) Why is the first ionization energy of sulfur smaller than the first ionization energy of phosphorus?
Answer: When sulfur loses one electron, it take on a particularly stable, half filled p subshell. The removal of this first electron therefore requires less energy than the removal of an electron from phosphorus initially half filled p subshell.
60) Why do Li, Na, and K have similar chemical properties?
Answer: They are in the same group (family) and all have the same number of valence electrons.
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61) Why does the size of the transition elements stay roughly the same as you move across a period?
Answer: The electrons added as the transition element increase in atomic number are NOT being added to the outermost shell. They are being added to an inner shell where they shield the outer electrons from nuclear charge. The number of outermost electrons are constant. For each electron added across the period, an additional proton is also added. This keeps the effective nuclear charge roughly constant as the transition elements increase in atomic number within a given period. Therefore, the size of the transition elements within a period stay roughly constant.
62) Below is a list of successive ionization energies (in kJ/mol) for a period 3 element. Identify the element and explain how you came to that conclusion.
IE2 = 2250 IE3 = 3360 IE4 = 4560 IE5 = 7010 IE6 = 8500 IE7 = 27,100
Answer: The large increase in ionization energy between IE6 and IE7 shows that there are 6 valence electrons in this element. The only period 3 element that contains 6 valence electrons is S.
63) Why do successive ionization energies increase?
Answer: After removing the first electron, the species possesses a positive charge. When trying to remove the second, third, fourth, etc... electrons you must add even more energy to overcome the attraction between the negative electron and the positively charged ion. As the ion becomes more positively charged, it becomes more difficult (higher energy cost) to separate an electron from the ion.
Match the following.
64) valence electrons A) 1
65) core electrons
66) 0
67) number of unpaired electrons in Ti2+
68) number of unpaired electrons in Na
64) D 65) E 66) B
B) number of unpaired electrons in Zn2+
C) 2
D) electrons in the outermost shell
67) C
E) electrons in completed shells
68) A
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