Deck 24: Complex Ions and Coordination Compounds

Question 1

A monodentate ligand can have only one lone pair of electrons.

Answer 1

False

Question 2

Some wavelengths of light are the correct energy to be used to promote electrons to higher energy levels and are thus lost from white light. The loss of these wavelengths causes solutions of transition elements to be colored.

Answer 2

True

Question 3

Which of the following metal ions has coordination numbers of 2 or 4?

A) Fe3+
B) Co3+
C) Cu+
D) Pt2+
E) Cr3+

Answer 3

Cu+

Question 4

Choose the INCORRECT formula/name combination for ligands.

A) C5H5N pyridine
B) F- fluoro
C) Cl- chloro
D) OH- hydroxo
E) I- iodino

Question 5

Choose the INCORRECT formula/name combination for ligands.

A) H2O aqua
B) NH3 ammine
C) CO carbonyl
D) NO nitrito-N-
E) CH3NH2 methylamine

Question 6

Unpaired electrons cause a complex ion to be diamagnetic.

Question 7

Which combination of central species and net charge is FALSE for complex ions or coordination compounds?

A) neutral metal atom, positive net charge
B) neutral metal atom, zero net charge
C) metal cation, zero net charge
D) metal cation, positive net charge
E) metal cation, negative net charge

Question 8

Enantiomers are isomers which are not chiral.

Question 9

Choose the INCORRECT statement.

A) A ligand that bonds to the metal ion with more than one atom is unidentate.
B) A chelate is produced by a ligand bonding to the metal ion with two or more donor atoms.
C) In coordination nomenclature, the cations are named before the anions.
D) In coordination nomenclature, the names of the ligands are followed by the name of the central metal ion.
E) Anionic ligands end in -o in coordination nomenclature.

Question 10

Choose the INCORRECT statement.

A) The coordination number is the number of ligands which can attach to a metal center.
B) A ligand supplies one or more electron pairs to bond to the metal ion.
C) The ligand-metal ion bond is a coordinate covalent bond.
D) A ligand is a Lewis base.
E) A ligand that donates a pair of electrons is multidentate.

Question 11

Choose the INCORRECT formula/name combination for ligands.

A) O2- hydroxo
B) NO nitrosyl
C) I- iodo
D) CN- cyano
E) SO42- sulfato

Question 12

Complex-ions in which ligands are interchanged very slowly are called labile.

Question 13

Sequestering is using a chelating agents to reduce a free cation concentration to the point that the cation will not react to form objectionable products.

Question 14

High spin refers to the maximum number of ligands attached to the metal ion.

Question 15

Choose the INCORRECT formula/name combination for ligands.

A) Br- bromo
B) S2O32- sulfato
C) NO2- bonded to N nitrito-N-
D) NO2- bonded to O nitrito-O-
E) en ethylenediamine N2NCH2CH2NH2

Question 16

The overall formation constant can be calculated by multiplying the constant for each step of the formation.

Question 17

Which of the following metal ions can have coordination numbers of either 4 or 6?

A) Ag+
B) Ca2+
C) Cu+
D) Ni2+
E) Au+

Question 18

Complex-ion formation can be described in terms of Br∅nsted-Lowry acid-base reactions.

Question 19

A complex is any species involving coordination of ligands to a metal center.

Question 20

The [Fe(CN)6]3- complex ion:

A) exhibits square planar geometry
B) is diamagnetic
C) exhibits octahedral geometry
D) has two unpaired electrons
E) has four unpaired electrons

Question 21

Which of the following ligands cannot act as a chelating agent?

A) nitrite ion
B) ethylenediamine
C) ethylenediaminetetracetate ion
D) hydrazine
E) oxalate ion

Question 22

Which complex ion possesses the largest number of unpaired electrons?

A) CoCl42-
B) Cr(NH3)62+
C) Cu(NH3)42+
D) Mn(CN)64-
E) Fe(H2O)63+

Question 23

It is known that the sulfhydryl group, -SH, forms strong coordinate bonds to certain heavy metal ions. Which of the following do you expect to be the best chelating agent for heavy metal ions?

A) HS-CH2-CH(SH)-CH2-OH
B) H-SH
C) CH3-SH
D) CH3-S-S-CH3
E) SO42-

Question 24

When [Ni(NH3)4]2+ is treated with concentrated HCl, two compounds having the same formula, Ni(NH3)4Cl2, designated I and II, are formed. Compound I can be converted to compound II by boiling it in dilute HCl. A solution of I reacts with oxalic acid, H2C2O4, to form Ni(NH3)4(C2O4). Compound II does not react with oxalic acid. Compound II is:

A) the cis isomer
B) tetrahedral in shape
C) the trans isomer
D) the same as compound I
E) octahedral in shape

Question 25

Choose the INCORRECT statement.

A) Structures that are nonsuperimposable mirror images are enantiomers.
B) Enantiomers are chiral.
C) Enantiomers are optical isomers.
D) Hydrates are molecules which do not react with water.
E) Coordination complexes add the ligands one at a time.

Question 26

Choose the INCORRECT statement about coordination nomenclature.

A) Molecular ligands carry the molecule's name.
B) The number of ligands is specified by a superscript.
C) Ligands are named in alphabetical order.
D) A Roman numeral designates the oxidation state of the metal ion.
E) Complex anions have an ate ending on the central metal's name.

Question 27

Which of the following is a bidentate ligand?

A) H2O
B) NO2-
C) NH3
D) H2NCH2CH2NH2
E) [(O2C)2NCH2CH2N(CO2)2]4-

Question 28

Which one of the following could be a chelating ligand?

A) NH3
B) CH3-CH2-NH2
C) NH2-CH2-CH2-NH2
D) any metal ion
E) CN-

Question 29

Which of the following ligand names is INCORRECT?

A) F-/fluoro
B) OH-/hydroxo
C) NH3/ammino
D) NO2-/nitrito
E) SO42-/sulfato

Question 30

Which element possesses the smallest number of unpaired electrons?

A) Co
B) Cr
C) Cu
D) Mn
E) Fe

Question 31

Choose the correct shape, weak or strong field, and number of unpaired electrons for [CoCl4]2-.

A) square planar, strong, 3
B) square planar, strong, 0
C) tetrahedral, strong, 1
D) tetrahedral, weak, 3
E) square planar, weak, 0

Question 32

Which of the following ligands exerts the strongest field?

A) I-
B) H2O
C) ONO-
D) NH3
E) Br-

Question 33

Choose the correct shape, weak or strong field, and number of unpaired electrons for [PtCl6]2-.

A) square planar, weak, 0
B) square planar, strong, 4
C) tetrahedral, weak, 0
D) octahedral, weak, 1
E) octahedral, weak, 4

Question 34

Choose the INCORRECT statement about isomers.

A) Structural isomers differ in structure or bond type.
B) stereoisomers differ in the spatial arrangements among the ligands.
C) Ionization isomers differ in the charge on the central ion.
D) Linkage isomers differ in which atom is bonded to the central atom.
E) Geometric isomerism is cis-trans isomerism.

Question 35

Coordination isomerism could be shown by ________.

A) Li[AlH4]
B) [Ag(NH3)2][CuCl2]
C) [Co(NH3)4Cl2]Br
D) [Pt(H2O)4Cl2]
E) [Fe(CN)6](NH3)3

Question 36

Choose the correct statement about isomers of [Pt(H2O)2(NH3)Cl]Br.

A) I is cis, II is trans.
B) The two molecules are the same.
C) The two molecules are the same but one is turned over.
D) They are not isomers.
E) I is trans, II is cis.

Question 37

Choose the correct shape, weak or strong field, and number of unpaired electrons for [Co(NH3)6]3+.

A) square planar, strong, 6
B) square planar, weak, 0
C) tetrahedral, strong, 0
D) octahedral, strong, 0
E) octahedral, weak, 6

Question 38

Choose the INCORRECT formula/name combination for ligands.

A) -O2C-CO2- oxalato (ox)
B) S2O32- thiosulfato
C) CH3NH2 ammino
D) SCN- bonded to S thiocyanato-S-
E) NCS- bonded to N thiocyanato-N-

Question 39

Choose the INCORRECT statement.

A) One popular chelating agent is EDTA.
B) [Cr(NH3)4Br]Cl and [Cr(NH3)4Cl]Br are examples of ionization isomerism.
C) [Zn(NH3)4][CuCl4] is an example of coordination isomerism.
D) A tetrahedral complex cannot have a geometric isomer.
E) Enantiomers are structural isomers.

Question 40

The compound PtCl2(en)2 [en = H2NCH2NH2] is octahedral; therefore we know that:

A) en must be a monodentate ligand
B) two moles of Cl- per mole of PtCl2(en)2 can be precipitated rapidly by the addition of Ag+
C) the molecule is nonpolar
D) the compound can have cis and trans isomers
E) Pt always has a coordination of 4

Question 41

Choose the correct shape, weak or strong field, and number of unpaired electrons for [Co(ox)3]4-.

A) tetrahedral, weak, 3
B) tetrahedral, strong, 3
C) square planar, strong, 3
D) octahedral, weak, 3
E) octahedral, strong, 5

Question 42

Using the stepwise formation constants given, calculate the net formation constant for the [Cu(H2NCH2CH2NH2)2]2+ complex. Cu2+ + en → [Cu(en)]2+ K1 = 5.2 × 1010
[Cu(en)]2+ + en → [Cu(en)2]2+ K2 = 2.0 × 109

A) 2.6 × 101
B) 2.5 × 109
C) 5.4 × 1010
D) 7.9 × 1019
E) 1.0 × 1020

Question 43

The hexaaquachromium(III) ion absorbs light in the green part of the visible spectrum, thereby appearing to have the color:

A) blue
B) cyan
C) green
D) purple
E) yellow

Question 44

In the cation [CoCl2(en)2]+, the oxidation state of cobalt and its coordination number, respectively, are ________.

A) -3 and two
B) +2 and six
C) +4 and four
D) +3 and six
E) -4 and six

Question 45

What is the concentration of Zn2+ if 0.254 g of ZnCl2 is dissolved in 200.0 mL of 2.00 M NH3? Kf ([Zn(NH3)4]2+) = 4.1 × 108

A) 0.0093 M
B) 1.5 × 10-12 M
C) 2.4 × 10-9 M
D) 2.3 × 10-12 M
E) 0.0019 M

Question 46

Choose the correct shape, weak or strong field, and number of unpaired electrons for [CoI6]3-.

A) tetrahedral, strong, 2
B) tetrahedral, weak, 4
C) square planar, strong, 0
D) octahedral, strong, 5
E) octahedral, weak, 4

Question 47

What is the concentration of Ag+ if 0.125 g of AgC2H3O2 is placed in 100.0 mL of 1.00 M NH3? Kf = 1.6 × 107 for [Ag(NH3)2]+

A) 4.8 × 10-10 M
B) 5.6 × 10-10 M
C) 8.0 × 10-8 M
D) 8.3 × 10-6 M
E) 7.5 × 10-3 M

Question 48

What is the approximate concentration of free Fe2+ remaining at equilibrium in a solution prepared by mixing 5.0 mL of 0.10 M FeSO4 with 5.0 mL of 2.0 M KCN? [The net formation constant for the hexacyanoferrate(II) ion is 1 × 1037.]

A) 3 × 10-22 M
B) 7 × 10-30 M
C) 4 × 10-38 M
D) 5 × 10-37 M
E) 4 × 10-40 M

Question 49

A compound has the empirical formula CoCl3 ∙ 5NH3. One mole of it yields two moles of silver chloride when treated with silver nitrate. Ammonia is not removed by treatment with concentrated sulfuric acid. A reasonable formula for the compound is ________.

A) [Co(NH3)5]Cl3
B) CoCl3 ∙ 5NH3
C) [Co(NH3)4Cl]Cl2 ∙ NH3
D) [Co(NH3)5Cl]Cl2
E) [Co(NH3)4Cl2]Cl ∙ NH3

Question 50

What is the approximate concentration of free Ni2+ remaining at equilibrium in a solution prepared by mixing 5.0 mL of 0.10 M NiCl2 with 5.0 mL of 2.0 M NH3(aq)? [The net formation constant for the hexamminenickel(II) ion is 5.5 × 108.]

A) 1.8 × 10-9 M
B) 7.7 × 10-10 M
C) 1.3 × 10-10 M
D) 2.4 × 10-10 M
E) 0.050 M

Question 51

If a central ion has a coordination number of 4 we might expect the geometry of the complex ion to be ________.

A) octahedral
B) cubical
C) trigonal bipyramidal
D) square planar
E) trigonal planar

Question 52

In the cation [CrCl2(H2O)4]+, the oxidation state of chromium and its coordination number, respectively, are ________.

A) -3 and two
B) +3 and six
C) 0 and four
D) +2 and six
E) -4 and six

Question 53

In the compound K4[Fe(CN)6], the oxidation state of iron and its coordination number, respectively, are ________.

A) -4 and ten
B) 0 and ten
C) +4 and four
D) +2 and six
E) -4 and six

Question 54

Choose the correct shape, weak or strong field, and number of unpaired electrons for [Co(NH3)4]2+.

A) octahedral, weak, 3
B) octahedral, strong, 3
C) square planar, strong, 1
D) tetrahedral, weak, 1
E) tetrahedral, strong, 1

Question 55

What is the approximate concentration of free Cu2+ remaining at equilibrium in a solution prepared by mixing 5.0 mL of 0.10 M CuCl2 with 5.0 mL of 2.0 M ethylenediamine? [The net formation constant for the bis(ethylenediaminecopper(II) ion is 1 × 1020.]

A) 9 × 10-22 M
B) 7 × 10-22 M
C) 2 × 10-22 M
D) 1 × 10-21 M
E) 6 × 10-22 M

Question 56

What is the concentration of Cu2+ if 0.235 g of CuCl2 is dissolved in 300.0 mL of 0.550 M NH3? Kf ([Cu(NH3)4]2+) = 1.1 × 1013

A) 5.8 × 10-15 M
B) 1.0 × 10-15 M
C) 6.9 × 10-15 M
D) 5.8 × 10-3 M
E) 1.2 × 10-12 M

Question 57

Choose the correct shape, weak or strong field, and number of unpaired electrons for [Ni(C2O4)3]4-.

A) square planar, strong, 4
B) octahedral, weak, 2
C) square planar, weak, 0
D) tetrahedral, weak, 0
E) octahedral, weak, 3

Question 58

Of the following complex ions, two appear violet in aqueous solution, one appears purple, one appears blue-green, and one appears yellow. Which is yellow?

A) [Cr(H2O)6]3+
B) [CrCl(H2O)5]2+
C) [CrCl(NH3)5]2+
D) [CrCl2(NH3)4]+
E) [Cr(NH3)6]3+

Question 59

What is the approximate concentration of free Ni2+ remaining at equilibrium in a solution prepared by mixing 5.0 mL of 0.10 M NiCl2 with 5.0 mL of 2.00 M ethylenediamine? [The net formation constant for the tris(ethylenediaminenickel(II) ion is 2.1 × 1018.]

A) 0.050 M
B) 1.4 × 10-19 M
C) 4.8 × 10-19 M
D) 3.9 × 10-20 M
E) 2.8 × 10-20 M

Question 60

What is the concentration of Ni2+ if 0.223 g of NiCl2 is dissolved in 250.0 mL of 0.760 M NH3? Kf ([Ni(NH3)6]2+) = 5.5 × 108

A) 6.9 × 10-3 M
B) 7.6 × 10-11 M
C) 1.3 × 10-11 M
D) 9.7 × 10-11 M
E) 1.4 × 10-11 M

Question 61

A compound has the empirical formula CoCl3 ∙ 5NH3. One mole of it yields three moles of silver chloride when treated with silver nitrate. Ammonia is not removed by treatment with concentrated sulfuric acid. A reasonable formula for the compound is ________.

A) [Co(NH3)5]Cl3
B) CoCl3 ∙ 5NH3
C) [Co(NH3)4Cl]Cl2 ∙ NH3
D) [Co(NH3)5Cl]Cl2
E) [Co(NH3)4Cl2]Cl ∙ NH3

Question 62

The two different compounds [Cu(NH3)4][Fe(CN)4(H2O)2] and [Cu(CN)4]Fe(NH3)4(H2O)2] are examples of ________.

A) optical isomers
B) linkage isomers
C) ionization isomers
D) geometric isomers
E) coordination isomers

Question 63

What is the correct IUPAC name for [AuCl4(H2O)2]-?

A) tetrachlorodiaquaaurate(III)
B) tetrachlorodiaquaaurate(I)
C) tetrachlorodiaquagold(III)
D) tetrachlorodiaquagold(I)
E) tetrachlorodiaquagoldate(III)

Question 64

Isomers such as the two forms of the ion [Co(NH3)2Cl4]- that differ only in the way the atoms are oriented in space are called, in general ________.

A) ionization isomers
B) crystal field isomers
C) hybridization isomers
D) optical isomers
E) cis-trans isomers

Question 65

What is the correct IUPAC name for [Co(NH3)6]2+?

A) hexammoniacobaltate(II)
B) hexaamminecobaltate(II)
C) hexammoniacobalt(II)
D) hexaamminecobalt(II)
E) hexaamminecobaltium(II)

Question 66

The correct formula of triamminediaquachlorocobalt (III) iodide is ________.

A) [Co(NH3)2(H2O)3Cl]I2
B) [Co(NH3)3(H2O)2Cl]I3
C) [Co(NH3)3(H2O)2Cl]I2
D) [Co(NH3)3(H2O)2Cl]I
E) [Co(NH3)3(H2O)2I]Cl2

Question 67

What is the correct IUPAC name for K3[Co(NO2)6]?

A) tripotassiumhexanitritocobalt(0)
B) tripotassiumhexanitritocobalt(III)
C) potassium hexanitritocobaltate(III)
D) potassium hexanitritocobalt(III)
E) potassium hexanitratocobalt(III)

Question 68

Write the correct formula for tetrachloroplatinate (II) ion.

A) [PtCl4]2-
B) PtCl3Cl
C) [Pt4Cl]-
D) [PtCl3]-Cl-
E) [PtCl2]42+

Question 69

Give the correct name for [Fe(CO)4].

A) tetracarbonyliron(0)
B) iron carbon monoxide
C) carbonylferrate(4)
D) tetracarbonylferrate(0)
E) iron carbonyl

Question 70

Give the correct name for [Fe(H2O)4(OH)2]+.

A) diaquotetrahydroxoiron(III)
B) tetrahydroxodiaquoferrate(III)
C) hydrated iron hydroxide
D) tetrawaterdihydroxoiron(III)
E) tetraaquadihydroxoiron(III)

Question 71

Give the correct name for [Ni(NH3)4]2+.

A) tetraamminonickelate(II)
B) nickel amine
C) tetraamminenickel(II)
D) nickel tetraamine
E) tetraamminonickel(4)

Question 72

The difference between coordination of Co2+ with NO2- by an oxygen-cobalt bonding compared to a nitrogen-cobalt bonding results in ________.

A) coordination isomers
B) geometric isomers
C) ionization isomers
D) linkage isomers
E) optical isomers

Question 73

Which of the following complexes has no geometric isomers?

A) [Pt(NH3)4F2]
B) [Pt(NH3)F5]-3
C) [Co(NH3)4F2]+
D) [Co(NH3)3F3]
E) [Co(NH3)2F4]-

Question 74

Conductivity experiments indicate that dichlorotetraamine-palladium (IV) chloride is composed of 3 moles of ions per mole of compound. However, only 2 moles of AgCl per mole of compound are precipitated rapidly when silver nitrate solution is added to a solution of the palladium compound.
What is the probable structure of the complex ion?

A) octahedral
B) square planar
C) tetrahedral
D) linear
E) trigonal planar

Question 75

What is the correct name of the following ion: [Zn(CN)4]2-

A) zinc quadracyanide
B) tetracyanozincate(II)
C) zinc cyanide
D) tetracyanozinc(II)
E) cyanozinc(4)

Question 76

Give the correct name for [Al(H2O)4]3+.

A) hydrated aluminum
B) aluminum hydrate
C) tetraaquoaluminate(6)
D) tetraaquaaluminum(III)
E) tetrawateraluminum(4)

Question 77

Give the correct name for [Fe(CN)6]4-.

A) hexayanoiron(II)
B) iron hexacyanide
C) hexacyanoferrate(II)
D) hexacyanide iron(II)
E) hexacyanoferrate(III)

Question 78

The correct name for [Ag(NH3)2]+ is ________.

A) silver amide
B) diamminesilver(I)ion
C) silver ammoniate
D) silver nitride
E) silver(I) diammine ion

Question 79

Give the correct name for [AuF4]-.

A) gold fluoride
B) tetrafluoroaurate(III)
C) gold tetrafluoride
D) tetrafluorogold(III)
E) tetrafluoride gold

Question 80

Molecules which are nonsuperimposable mirror images of each other are called ________.

A) achiralomers
B) enantiomers
C) diastereomers
D) cis/trans isomers
E) geometers