Periodic trends (and a few more chapter 8) practice problems
1) Which of the following orbitals can be derived from the following quantum numbers:
n = 2, l = 1, ml = -1
A) 2p x
B) 2p z
C) 2s
E) 2d x 2-y2
D) 2d xz
2) Which of the following orbitals can be derived from the following quantum numbers:
n = 3, l = 2, ml = -2
A) 3p x
B) 3p z
C) 3d z2
E) 3d x 2-y2
D) 3d xz
3) The 3dz2 orbital is specified by which of the following sets of quantum numbers?
A) n = 3, l = 2, ml = 1
B) n = 3, l = 1, ml = 0
C) n = 3, l = 2, ml = 0
D) n = 3, l = 1, ml =1
4) Which of the following orbitals would have 2 angular nodes and 1 radial node?
A) 3p
B) 4p
C) 3d
D) 4d
E) 4f
5) Below is the radial wave function for a particular n = 4 hydrogen orbital. Which radial wave function is it?
A) 4s
B) 4p
C) 4d
D) 4f
6) Identify the following radial wave function (not a radial distribution) below.
A) 1s
B) 2s
C) 2p
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D) 3p
E) 3d
7) What is the complete ground state electron configuration for Cr.
8) What is the abbreviated ground state electron configuration for W.
9) What is the abbreviated ground state electron configuration for La.
10) What is the abbreviated ground state electron configuration for Ti2 .
11) What is the abbreviated ground state electron configuration for Zn2 .
12) What is the abbreviated ground state electron configuration for Cr3 .
13) What is the abbreviated ground state electron configuration for Zr2 .
14) Which ion does not have a true noble gas electron configuration in its ground state?
A) Sc3+
B) Al3+
C) Ga3+
D) As3-
E) F-
15) Which group contains species that are not isoelectronic?
A) Si4+, Ar, Ca2+
B) Se2-, Br- , Kr
C) Cl- , K+, V3+
D) Ti4+ , V5+, Cr6+
E) Mn4+, Fe3+, Co2+
16) How many electrons will nitrogen gain or lose when it forms an ion?
A) lose 3
B) lose 2
C) gain 3
D) lose 1
E) lose 2 or 3
17) How many electrons will aluminum gain or lose when it forms an ion?
A) lose 2
B) lose 1
C) lose 3
D) gain 3
E) lose 2 or 3
18) Which of the following statements is TRUE?
A) An orbital that penetrates into the region occupied by core electrons is more shielded from nuclear charge
and therefore has a lower energy.
B) An orbital that penetrates into the region occupied by core electrons is more shielded from nuclear charge
and therefore has a higher energy.
C) An orbital that penetrates into the region occupied by core electrons is less shielded from nuclear charge
and therefore has a higher energy.
D) An orbital that penetrates into the region occupied by core electrons is less shielded from nuclear charge
and therefore has a lower energy.
19) Choose the statement that is TRUE.
A) Shielding only occurs in hydrogen or hydrogen-like ions that have only one electron.
B) Within a given energy level; f electrons screen the best, followed by d, then p, then s.
C) Outer electrons in the same subshell efficiently shield one another from nuclear charge.
D) Core electrons efficiently shield outer electrons from nuclear charge.
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20) Which of the following occurs for the representative elements going left to right across the period?
A) electronegativity decreases
B) atomic size increases
C) atomic size remains constant
D) the outer electrons are held more weakly
E) attraction between outer electrons and the nucleus increases because Zeff increases
21) Which of the following statements is NOT true?
A) Ionization energy increases from left to right through a period of elements.
B) Atomic radius decreases from left to right through a period of elements.
C) Atomic radius increases down a group.
D) Anions are always larger than the atoms from which they are formed.
E) Cations are always larger than the atoms from which they are formed.
22) Which of the following has the largest atomic radius?
A) I
B) Br
C) Mo
D) Ca
E) Rb
D) Cu2+
E) Al3+
D) K+
E) Ca2+
23) Place the following elements in order of increasing atomic radius.
P
Ba Cl
24) Place the following elements in order of decreasing atomic radius.
Xe Rb Ar
25) Which of the following has the largest radius?
A) BrB) Kr
C) Se2-
26) Which of the following isoelectronic species has the largest radius?
A) P3B) S2C) Cl27) Place the following in order of increasing radius.
Ca2
S2
Cl
28) Place the following in order of increasing radius.
Br
Na
Rb
29) Which of the following pairs would you expect to have very similar radii?
A) Mo and W
B) H and He
C) Ne and Ar
D) O and F
E) Fe and Ru
30) What is the general relationship between ionization energy and atomic radii?
A) Ionization energy increases as radii increases.
B) Ionization energy decreases as radii decreases.
C) Ionization energy decreases as radii increases.
D) There is no relationship.
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31) 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
O2 (g)
E) O (g) + e
32) Which reaction below represents the second ionization of Sr?
A) Sr(g)
Sr (g) + e
2
Sr (g)
B) Sr (g) + e
C) Sr (g) + e
Sr(g)
Sr2 (g)
D) Sr (g) + e
Sr2 (g) + e
E) Sr (g)
33) 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)
34) Which reaction below represents the second electron affinity of S?
A) S(g) + e
S (g)
S2 (g)
B) S (g) + e
C) S(g)
S (g) + e
D) S (g)
S(g) + e
2
S (g) + e
E) S (g)
35) What period 3 element would be predicted to have 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
36) Choose the species from which one electron could most easily be removed.
A) Ar
B) K+
C) K
D) Ca
37) Why is the electron affinity so small for group 18 elements?
A) Adding an electron to a noble gas would cause an explosion.
B) Electrons can't be added to a gas.
C) The added electron would have to be added into the d subshell.
D) An added electron would have to be added into a stable half-filled p subshell.
E) An added electron would have to go into a new subshell in a higher energy level.
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E) Mg
E) Cl
38) Why is the electron affinity so small for the group 2 elements?
A) Electrons can't be added to metals.
B) An added electron would have to be added into the half-filled p subshell.
C) The group 2 elements are all diatomic elements.
D) An added electron would have to be added into a new subshell.
39) Why is the electron affinity so small for for nitrogen?
A) Electrons can't be added to gases.
B) The added electron would have to be added into the p subshell.
C) The added electron would have to be added into a higher energy level.
D) The added electron would have to go into a new subshell.
E) The added electron would have to be added into a relatively stable half-filled p subshell.
40) Among the alkali metals, cesium reacts more rapidly than sodium because:
A) cesium can make more bonds
B) cesium has more electrons
C) the valence electrons of cesium are at a greater average distance from the nucleus causing them to be
harder to remove
D) the valence electrons of cesium are at a greater average distance from the nucleus enabling them to be
pulled off easier
41) Place the following in order of decreasing metallic character.
C
A) O > N > F
B) F > O > N
C) C > N > O
D) F > N > O
E) N > C > O
>
>
>
>
>
O
N F
C
C
F
C
F
42) Identify the alkali metal that is most reactive with water.
A) Li
B) Na
C) K
D) Rb
E) Cs
43) Identify a characteristic of halogens.
A) powerful reducing agents
B) forms water in reactions
C) powerful oxidizing agents
D) absorbs water in reactions
E) inert
TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.
44) Nitrogen has a higher ionization energy and electron affinity than oxygen.
45) The ionization energy is the energy for an uncharged gaseous atom or ion to lose an electron.
46) Electron affinities have the same magnitude as ionization energies, but opposite signs.
47) The electron affinity is the energy released (usually) as an uncarged gaseous atom gains an electron.
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