Deck 23: Transition Metals Chemistry and Coordination Compounds

Question 1

The electron configuration of a Ti atom is

A) [Ne]3s²3d².
B) [Ne] 3s²4d².
C) [Ar]4s²3d².
D) [Ar]4s²4d².
E) [Ar]3d⁴.

Answer 1

[Ar]4s²3d².

Question 2

The electron configuration of an Fe²⁺ ion is

A) [Ar]4s²4d⁴.
B) [Ar]4s²3d⁶.
C) [Ar]3d³.
D) [Ar]3d⁵.
E) [Ar]3d⁶.

Answer 2

[Ar]3d⁶.

Question 3

In Na₃[Ni(SCN)₅], how many 3d electrons does nickel have

A) 6
B) 7
C) 8
D) 9
E) 10

Answer 3

8

Question 4

The total number of electrons in the 3d orbitals of Ti³⁺ is

A) 0.
B) 1.
C) 2.
D) 3.
E) 4.

Question 5

The total number of electrons in the 3d orbitals of Cr³⁺ is

A) 1.
B) 2.
C) 3.
D) 4.
E) 5.

Question 6

The electron configuration of a Co³⁺ ion is

A) [Ar]3d⁶.
B) [Ar]4s¹3d⁵.
C) [Ar] 4s²3d⁴.
D) [Ar]3d⁵.
E) [Ar]3d⁴.

Question 7

How would you expect the molecule 1,10-phenanthroline (shown below) to function as a ligand

A) It would be expected to be a monodentate ligand.
B) It would be expected to be a bidentate ligand.
C) It would be expected to be a tridentate ligand.
D) It would be expected to be a tetradentate ligand.
E) It would not be expected to function as a ligand.

Question 8

The total number of electrons in the 3d orbitals of a titanium atom is

A) 1.
B) 2.
C) 3.
D) 4.
E) 5.

Question 9

In [Cu(NH₃)₄]CO₃, how many 3d electrons does copper have

A) 6
B) 7
C) 8
D) 9
E) 10

Question 10

How many 3d electrons does a V³⁺ ion have

A) 6
B) 5
C) 4
D) 3
E) 2

Question 11

Which of the following choices can function as a bidentate ligand

A) PH₃
B) Cl^-
C) CN^-
D) ^-OCH₂CH₂CH₂O^-
E) CO

Question 12

In the complex ion [Fe(CN)₆]^4-, the oxidation number of Fe is

A) +1.
B) +2.
C) +3.
D) -4.
E) +6.

Question 13

The total number of electrons in the 3d orbitals of Co³⁺ is

A) 4.
B) 5.
C) 6.
D) 7.
E) 10.

Question 14

Assuming a coordination complex is formed with Fe²⁺ and 1,10-phenanthroline (shown below), which of the following statements is true

A) If two 1,10-phenanthroline molecules are coordinated to the iron ion, then the coordination number is 2.
B) If two 1,10-phenanthroline molecules are coordinated to the iron ion, then the coordination number is 6.
C) If three 1,10-phenanthroline molecules are coordinated to the iron ion, then the coordination number is 3.
D) If three 1,10-phenanthroline molecules are coordinated to the iron ion, then the coordination number is 6.
E) If four 1,10-phenanthroline molecules are coordinated to the iron ion, then the coordination number is 4.

Question 15

In K₄[Fe(CN)₆], how many 3d electrons does the iron atom have

A) 3
B) 4
C) 5
D) 6
E) 7

Question 16

The total number of electrons in the 3d orbitals of a copper atom is

A) 6.
B) 7.
C) 8.
D) 9.
E) 10.

Question 17

The electron configuration of a nickel atom is

A) [Ar]4s²3d⁶.
B) [Ar]4s¹3d⁷.
C) [Ar]3d⁸.
D) [Ar]4s²3d⁸.
E) [Ar]3d¹⁰.

Question 18

How many 3d electrons does a Mn²⁺ ion have

A) 1
B) 2
C) 3
D) 4
E) 5

Question 19

Which of the following choices can function as a monodentate ligand only

A) (H₂NCH₂CH₂NH₂)
B) (^-O₂CCO₂^-)
C) (H₂O)
D) (^-OCH₂CH₂CH₂O^-)
E) (H₂PCH₂CH₂PH₂)

Question 20

The electron configuration of a Cr³⁺ ion is

A) [Ar]3d⁵.
B) [Ar]4s¹3d².
C) [Ar]3d³.
D) [Ar]4s¹3d⁵.
E) [Ar]4s²3d⁴.

Question 21

Which of these square planar complex ions can have cis-trans isomers

A) [Pt(NH₃)₄]²⁺
B) [Ni(NH₃)₄]²⁺
C) [Pt(NH₃)₂Cl₂]
D) [Pt(NH₃)Cl₃]^-
E) [Ni(NH₃)₃Cl]⁺

Question 22

The best name for the complex shown below is

A) cobalt(III)bis(ethylenediamine) bromide.
B) dibromobis(ethylenediamine)cobalt(III) bromide.
C) dibromidedi(ethylenediamine)cobalt(III) bromide.
D) dibromodiethylenediaaminecobalt(III) bromide.
E) tribromobis(ethylenediamine)cobalt(III).

Question 23

Which response gives the correct coordination number (C.N.) and oxidation number (O.N.) of the transition metal atom in [Co(NH₃)₂(H₂O)₂Cl₂]⁺

A) C.N. = 2; O.N. = +3
B) C.N. = 3; O.N. = +1
C) C.N. = 4; O.N. = +2
D) C.N. = 6; O.N. = +1
E) C.N. = 6; O.N. = +3

Question 24

Which of these octahedral complexes can have cis-trans isomers

A) Co(NH₃)₃Cl₃
B) [Co(NH₃)₅Cl]Cl₂
C) [Co(NH₃)₆]Cl₃
D) Na₃[CoCl₆]
E) Na₂[Co(NH₃)Cl₅]

Question 25

The best name for K₄[FeCl₂(CN)₄] is

A) tetrapotassium dichlorodicyanoiron(II).
B) potassium dichlorodicyanoiron(II).
C) potassium dichlorodicyanoferrate(III).
D) tetrapotassium dichlorobis(cyano)iron(III).
E) potassium dichlorotetracyanoferrate(II).

Question 26

The coordination compound shown below has

A) two monodentate ligands and two bidentate ligands.
B) three monodentate ligands and two bidentate ligands.
C) four monodentate ligands and two bidentate ligands.
D) one monodentate ligand and four bidentate ligands.
E) four bidentate ligands.

Question 27

In the coordination compound [Co(en)₂Cl₂]Cl, the coordination number and oxidation number of the central atom are, respectively,

A) 4, +3.
B) 6, +2.
C) 4, +2.
D) 6, +3.
E) 4, +1.

Question 28

In the complex ion [Co(en)₂Br₂]⁺, the oxidation number of Co is

A) +1.
B) +2.
C) +3.
D) -2.
E) -1.

Question 29

Give the coordination number (C.N.) and oxidation number (O.N.) of the metal atom in the coordination compound [Cr(NH₃)₂(en)Cl₂].

A) C.N. = 4; O.N. = +2.
B) C.N. = 5; O.N. = +3.
C) C.N. = 5; O.N. = +2.
D) C.N. = 6; O.N. = +3.
E) C.N. = 6; O.N. = +2.

Question 30

The correct name for Fe(CO)₅ is:

A) pentacarbonyliron(V)
B) pentacarbonyliron(0)
C) hexacarbonyliron(0)
D) hexacarbonyliron(V)
E) pentacarbonateiron(0)

Question 31

In the coordination compound [Pt(NH₃)₂Cl₂], the coordination number and oxidation number of the central atom are, respectively,

A) 2, 0.
B) 4, 4.
C) 5, 0.
D) 4, 2.
E) 6, 2.

Question 32

The correct formula for dicarbonylsilver (I) ion is:

A) Ag(CO)₂
B) [Ag(CO)₂]⁺
C) [Ag(CO)₂]^-
D) [Ag(CO)₂]²⁺
E) [Ag(CO)₂]^2-

Question 33

In the coordination compound K₂[Co(en)Cl₄], the coordination number (C.N.) and oxidation number (O.N.) of cobalt are

A) C.N. = 6; O.N. = +2.
B) C.N. = 6; O.N. = +3.
C) C.N. = 5; O.N. = +2.
D) C.N. = 5; O.N. = +4.
E) C.N. = 4; O.N. = +3.

Question 34

The correct formula for pentaamminechloroplatinum(IV) chloride is:

A) [Pt(NH₃)₅Cl]Cl₃
B) [Pt(NH₃)₅Cl]Cl₂
C) [Pt(NH₃)₅]Cl₃
D) [Pt(NH₃)₅Cl]Cl₄
E) [Pt(NH₃)₅]Cl₄

Question 35

The correct name for K₃[Fe(C₂O₄)₃] is:

A) tripotassium trioxalatoiron(III)
B) potassium trioxalatoiron(II)
C) potassium trioxalatoiron(III)
D) tripotassium oxalatoiron(0)
E) potassium trioxalateiron(II)

Question 36

The correct formula for the dichlorobis(ethylenediamine)chromium(III) ion is

A) [Cr(en)₂Cl₂]³⁺.
B) [Cr(en)Cl₂]⁺.
C) [Cr(en)₂Cl₂]²⁺.
D) [Cr(en)₂Cl₂]⁺.
E) [Cr(en)₃Cl₂]⁺.

Question 37

In the complex ion [Cr(C₂O₄)₂(H₂O)₂]^-, the oxidation number of Cr is

A) +1.
B) +2.
C) +3.
D) -2.
E) -1.

Question 38

The correct formula for sodium tetracyanonickelate(II) ion is:

A) Ni(CN)₄
B) [Ni(CN)₄]⁺
C) [Ni(CN)₄]²⁺
D) [Ni(CN)₄]^-
E) [Ni(CN)₄]^2-

Question 39

In the coordination compound [Cr(NH₃)(en)₂Cl]Br₂, the coordination number (C.N.) and oxidation number (O.N.) of the metal atom are, respectively,

A) C.N. = 6; O.N. = +4.
B) C.N. = 6; O.N. = +3.
C) C.N. = 5; O.N. = +2.
D) C.N. = 4; O.N. = +2.
E) C.N. = 4; O.N. = +3.

Question 40

The correct name for [Fe(CO)₆]Br₃ is:

A) hexacarbonyliron(II) bromide
B) hexacarbonyliron(III) bromide
C) hexacarbonyltribromoiron(III)
D) hexacarbonyltribromoiron(II)
E) hexacarbonyliron(III) tribromide

Question 41

Which one of these complex ions would absorb light with the shortest wavelength

A) [Co(H₂O)₆]²⁺
B) [Co(NH₃)₆]²⁺
C) [CoF₆]^4-
D) [Co(CN)₆]^4-
E) [Co(en)₆]²⁺

Question 42

Which of these ligands produces the strongest crystal field

A) Cl^-
B) CO
C) OH^-
D) H₂O
E) NH₃

Question 43

Two complex ions containing Ni are [Ni(NH₃)₆]²⁺, which is blue, and [Ni(en)₃]²⁺, which is purple. Which one of these statements is true

A) The crystal field splitting energy (D) is greater for [Ni(NH₃)₆]²⁺ than for [Ni(en)₃]²⁺.
B) [Ni(en)₃]²⁺ absorbs light in the violet region of the spectrum.
C) Both complex ions are diamagnetic.
D) The energy of the photon absorbed by [Ni(en)₃]²⁺ is greater than that absorbed by [Ni(NH₃)₆]²⁺.
E) The wavelength of the light absorbed by [Ni(en)₃]²⁺ is greater than the wavelength absorbed by [Ni(NH₃)₆]²⁺.

Question 44

Which of these ligands produces the weakest crystal field

A) CN^-
B) I^-
C) OH^-
D) H₂O
E) NH₃

Question 45

In the complex ion [ML₆]ⁿ⁺, Mⁿ⁺ has seven d electrons and L is a strong field ligand. According to crystal field theory, the magnetic properties of the complex ion correspond to how many unpaired electrons

A) 0
B) 1
C) 2
D) 3
E) 5

Question 46

How many unpaired electrons does the manganese ion have in [Mn(CN)₆]^4-

A) 1 unpaired electron
B) 2 unpaired electrons
C) 3 unpaired electrons
D) 5 unpaired electrons
E) No unpaired electrons

Question 47

In the complex ion [ML₆]ⁿ⁺, Mⁿ⁺ has five d electrons and L is a strong field ligand. According to crystal field theory, the magnetic properties of the complex ion correspond to how many unpaired electrons

A) 0
B) 1
C) 2
D) 3
E) 5

Question 48

Which of these complex ions would absorb light with the longest wavelength

A) [Co(H₂O)₆]²⁺
B) [Co(NH₃)₆]²⁺
C) [CoF₆]^4-
D) [Co(CN)₆]^4-
E) [Co(en)₆]²⁺

Question 49

Consider the [CoCl₆]^4- ion. Determine which responses are true statements.
I. The oxidation number of Co is -4.
II. The coordination number of cobalt is 6.
III. It is paramagnetic.
IV. It is a low-spin complex.

A) I, II, III, IV
B) I, IV
C) II, III
D) I, III
E) III, IV

Question 50

The ion [Co(NH₃)₆]²⁺ is octahedral and high spin. This complex is

A) paramagnetic, with 1 unpaired electron.
B) paramagnetic, with 3 unpaired electrons.
C) paramagnetic, with 4 unpaired electrons.
D) paramagnetic, with 5 unpaired electrons.
E) diamagnetic.

Question 51

In the complex ion [ML₆]ⁿ⁺, Mⁿ⁺ has seven d electrons and L is a weak field ligand. According to crystal field theory, the magnetic properties of the complex ion correspond to how many unpaired electrons

A) 0
B) 1
C) 2
D) 3
E) 5

Question 52

A complex with the composition [MA₂B₂]X₂ is found to have no geometrical isomers. Both A and B are monodentate ligands. The structure of the complex is

A) linear.
B) square planar.
C) tetrahedral.
D) octahedral.

Question 53

Which of the following complexes has optical (chiral) isomers

A) [Co(H₂O)₄Br₂]⁺
B) [Co(en)Cl₄]^-
C) [Co(en)(H₂O)₄]³⁺
D) [Co(en)₂Cl₂]⁺
E) Co(H₂O)₃Cl₃

Question 54

The number of geometrical isomers and optical isomers of the complex ion [Co(en)₃]³⁺ are, respectively,

A) 2 and 2.
B) 1 and 1.
C) 3 and 2.
D) 1 and 2.
E) 2 and 4.

Question 55

Which of the following complexes has optical (chiral) isomers

A) [Co(NH₃)₄Br₂]⁺
B) [Co(en)₃]³⁺
C) Co(NH₃)₃Br₃
D) [Co(en)Br₄]^-
E) [Co(en)(NH₃)₄]³⁺

Question 56

Two well-known complex ions containing Ni are [Ni(H₂O)₆]²⁺, which is green, and [Ni(en)₃]²⁺, which is purple. Which one of these statements is true

A) The crystal field splitting energy (D) is greater for [Ni(en)₃]²⁺ than for [Ni(H₂O)₆]²⁺.
B) [Ni(en)₃]²⁺ absorbs energy in the red region of the spectrum.
C) Both complex ions are diamagnetic.
D) [Ni(H₂O)₆]²⁺ transmits light with wavelengths of approximately 650-700 nm.
E) The green complex absorbs green light.

Question 57

Which of these electron energy level patterns would absorb light with the shortest wavelength

A) A
B) B
C) C
D) D

Question 58

How many unpaired electrons are there in the complex ion [Mn(CN)₆]^3-

A) 0
B) 1
C) 2
D) 3
E) 4

Question 59

In the complex ion [ML₆]ⁿ⁺, Mⁿ⁺ has six d electrons and L is a weak field ligand. According to crystal field theory, the magnetic properties of the complex ion correspond to how many unpaired electrons

A) 0
B) 1
C) 2
D) 3
E) 4

Question 60

Labile complexes are coordination complexes that

A) are labeled with a radioactive isotope.
B) are thermodynamically stable.
C) are thermodynamically unstable.
D) undergo rapid ligand exchange reactions.
E) undergo very slow ligand exchange reactions.

Question 61

Cis-platinum complexes are

A) used in the extraction of silver and gold.
B) effective antidotes for heavy metal poisoning (e.g., Pb²⁺ and Hg²⁺).
C) used to provide nutrients for plants.
D) used to prevent eutrophication of lakes.
E) effective antitumor agents.

Question 62

The chemical formula of the dibromobis(oxalato)cobaltate(III) ion is:
[CoBr₂(C₂O₄)₂]^3-

Question 63

How many geometric isomers are possible for the complex [CrF₃Br₃]^3-

A) None, only one structure is possible
B) Two
C) Three
D) Four
E) None of the above

Question 64

The correct labels for the geometric isomers of [CrF₂Cl₄]^3- shown here are (from left to right) trans and cis.

Question 65

What is the coordination number of silver in [Ag(NH₃)₂]Cl

A) 2
B) 4
C) 6
D) 8
E) None of the above

Question 66

A molecule or ion that provides an electron pair for coordinate covalent bond formation is called a Lewis acid.

Question 67

Copper can be separated from iron in the ore chalcopyrite (CuFeS₂) by heating the ore in the presence of oxygen to form copper(I) sulfide, iron(II) oxide, and one other product. Complete the following partially balanced equation by deciding both the identity of the missing compound and the number of moles required to balance the equation. (Note, no other coefficients are allowed to be changed.)
2CuFeS₂(s) + 4O₂(g) $\rarr$ Cu₂S(s) + 2FeO(s) + _____

A)2SO₃(g)
B)3SO₃(g)
C)2SO₂(g)
D)3SO₂(g)
E)None of the above

Question 68

What is the oxidation number of Co in the complex Co(H₂O)₃Cl₃

A) +1
B) +2
C) +3
D) +4
E) None of the above

Question 69

The correct name of the complex ion [Ni(CN)₄]^2- is:
tetracyanonickelate(II) ion

Question 70

The chemical formula of triammineaquodichlorochromium(III) chloride is:
[Cr(NH₃)₃(H₂O)Cl₂]Cl

Question 71

What is the coordination number of cobalt in [Co(NH₃)₆]Cl₃

A) 2
B) 4
C) 6
D) 8
E) None of the above

Question 72

The chemical formula of diamminedichloroplatinum(II) is:
Pt(NH₃)₂Cl₄

Question 73

The terms that describe the geometric isomers that are possible for the complex [CrF₂Cl₄]^3- are cis and trans.

Question 74

What is the oxidation number of Co in the complex [Co(H₂O)₄Cl₂]Cl

A) +1
B) +2
C) +3
D) +4
E) None of the above

Question 75

What is the oxidation number of cobalt in [Co(NH₃)₆]Cl₃

A) +1
B) +2
C) +3
D) +4
E) None of the above

Question 76

A molecule or atom that accepts an electron pair to form a coordinate covalent bond is called a Lewis base.

Question 77

What is the coordination number of chromium in Cr(en)₂Cl₂

A) 2
B) 4
C) 6
D) 8
E) None of the above

Question 78

What is the oxidation number of Co in the complex Na[Co(H₂O)₂Cl₄]

A) +1
B) +2
C) +3
D) +4
E) None of the above

Question 79

What is the oxidation number of Fe in [Fe(CN)₆]^4-

A) +1
B) +2
C) +3
D) +4
E) None of the above

Question 80

Ethylenediaminetetraacetic acid (EDTA) is

A) not useful as a chelating agent.
B) an effective antidote for heavy metal poisoning (e.g., Pb²⁺ and Hg²⁺).
C) a monodentate ligand.
D) known to form unstable complex ions with Fe³⁺, Hg²⁺, and Zn²⁺.
E) known to form complexes with platinum that inhibit the growth of cancerous cells.