Deck 21: Transition Metals and Coordination Chemistry

Question 1

Transition metals display great similarities

A)within a given period
B)within a given vertical group
C)with the semimetals
D)all of these
E)A and B only

Answer 1

A and B only

Question 2

The phenomenon called __________ contraction is responsible for the great similarity in atomic size and chemistry of 4d and 5d elements.

A)transition
B)coordination
C)lanthanide
D)isomeric
E)none of these

Answer 2

lanthanide

Question 3

The electron configuration of Ti²⁺ is

A)[Ar] 4s²
B)[Ar] 4s¹3d¹
C)[Ar] 3d²
D)[Ar] 4s²3d²
E)none of these

Answer 3

[Ar] 3d²

Question 4

What is the electron configuration of the Sc(I)ion?

A)[Ar] 4s¹4d¹
B)[Ar] 4s¹3d¹
C)[Ar] 3s¹3d¹
D)[Ar] 4s²
E)[Ar] 3d²

Question 5

Which metal ion has a d⁵ electron configuration?

A)Cr²⁺
B)Ag⁺
C)Mn²⁺
D)Os²⁺
E)Co²⁺

Question 6

What is the electron configuration of the Mn(II)ion?

A)[Ar] 4s²3d⁵
B)[Ar] 4s¹3d⁵
C)[Ar] 4s²3d³
D)[Ar] 3d⁵
E)none of these

Question 7

Which of the following is true?

A)The first ionization energy for Zn is significantly higher than that of Sc.
B)The first ionization energy for Zn is significantly lower than that of Sc.
C)The third ionization energy for Zn is significantly higher than that of Sc.
D)The third ionization energy for Zn is significantly lower than that of Sc.
E)Two of these are correct.

Question 8

A complex ion is a charged species consisting of a metal ion surrounded by

A)other transition metals
B)hydrogen ions
C)ligands
D)ligands and counter ions
E)none of these

Question 9

The electron configuration for Cr²⁺ is

A)[Ar] 4s²3d⁴
B)[Ar] 4s¹3d⁵
C)[Ar] 3d⁴
D)[Ar] 4s²3d²
E)none of these

Question 10

Which of the following transition metals are important to the U.S.economy and defense?

A)chromium and cobalt
B)manganese
C)platinum and palladium
D)all of these
E)A and B only

Question 11

Which of the transition metals is the best conductor of heat and electric current?

A)copper
B)silver
C)gold
D)tungsten
E)titanium

Question 12

How many ligands are in this representative drawing of a complex ion?

A)1
B)3
C)6
D)7
E)8

Question 13

Why do transition metals show a lot of chemical similarities within a given period?

A)The valence s and p electrons affect their chemistry more so than the inner d and f electrons,which do not participate in bonding as easily.
B)The number of electrons within a given period varies only slightly and is sometimes identical because these metals have more than one ionic form.
C)All elements in a given period,including the representative elements,have a lot of chemical similarities due to the gradual increase in atomic number.
D)The transition metals always fill their s and p orbitals first before filling their d orbitals,which affects their chemistry.
E)None of the above is correct.

Question 14

Which of the following is incorrect concerning the 3d,4d,and 5d transition series?

A)There is a significant increase in radius in going from the 3d to the 4d metals,but the 4d and 5d metals are similar in size.
B)There is a general decrease in size going from left to right for each of these series due to the increasing nuclear charge.
C)The separation of hafnium and zirconium found together in nature is difficult due to their similarities in chemistry,which is attributed to their virtually identical sizes.
D)Cerium through lutetium exhibits what is referred to as the lanthanide contraction.
E)All of the above are correct.

Question 15

Which of the following transition metals is most likely to form an oxide?

A)gold
B)silver
C)platinum
D)palladium
E)copper

Question 16

What is the electron configuration of the Ni(II)ion?

A)[Ar] 4s²3d⁶
B)[Ar] 4s¹3d⁷
C)[Ar] 4s²3d⁸
D)[Ar] 3d⁸
E)none of these

Question 17

The electron configuration of Cr³⁺ is

A)[Ar] 4s²3d¹
B)[Ar] 4s¹3d²
C)[Ar] 3d³
D)[Ar] 4s²3d⁴
E)none of these

Question 18

Which of the following is a d⁷ ion?

A)Co(II)
B)Cu(II)
C)Mn(II)
D)Mn(IV)
E)At least two of the above (a-d)are d⁷ ions.

Question 19

What is the maximum oxidation state expected for manganese?

A)+2
B)+8
C)+6
D)+5
E)+7

Question 20

The reducing abilities of the first-row transition metals generally __________ going from left to right across the period.

A)decrease
B)increase
C)stay the same
D)none of these
E)remain at 1.0 V

Question 21

Co²⁺ in water is blue.

Question 22

What transition metal is used in magnets,catalysts,and drill bits?

A)nickel
B)copper
C)platinum
D)cobalt
E)titanium

Question 23

How many d electrons are present on the metal ion in the complex ion PtCl₆^2-?

A)8
B)6
C)4
D)3
E)2

Question 24

What are the oxidation numbers of each central metal atom in the following coordination compounds? K₃[Fe(CN)₆],[Cr(NH₃)₄Br₂]Br,[Ni(H₂O)₆]Cl₂,Na₂[TaF₇]

A)3,3,3,5
B)3,3,2,7
C)-3,3,2,5
D)-3,1,2,5
E)3,3,2,5

Question 25

This transition metal is used in the production of a hard steel used for rock crushers and bank vaults,and can be found in nodules on the ocean floor.

A)iron
B)manganese
C)magnesium
D)cobalt
E)nickel

Question 26

Which 3d transition metal is mixed with concentrated sulfuric acid to give a powerful cleaning solution for removing organic materials from analytical glassware?

A)chromium
B)iron
C)cobalt
D)scandium
E)manganese

Question 27

What transition metal has the combination of toughness,stretchability,and resilience that makes it ideal for use in bicycle frames?

A)titanium
B)platinum
C)tungsten
D)nickel
E)aluminum

Question 28

The election configuration of Mn²⁺ is [Ar] 4s²3d³.

Question 29

What heavy metal is the most abundant and most important to our civilization?

A)iron
B)gold
C)magnesium
D)cobalt
E)copper

Question 30

Which of the metal ions in the following complex ions has a d⁵ electron configuration?

A)V(H₂O)₆²⁺
B)Mo(NH₃)₆³⁺
C)Co(CN)₄^-
D)Fe(CN)₆^3-
E)RhCl₆^4-

Question 31

The expected electron configuration of Cu⁺ is [Ar] 3s¹3d⁹.

Question 32

An element that is a significant component of both brass and bronze is:

A)nickel
B)tin
C)copper
D)iron
E)zinc

Question 33

The metals with the highest ionization energies are most likely to be found in nature in the elemental state.

Question 34

Which transition metal is valued for its high electrical conductivity and resistance to corrosion,and is widely used for plumbing?

A)iron
B)manganese
C)magnesium
D)cobalt
E)copper

Question 35

What transition metal is mainly used for galvanizing steel?

A)iron
B)zinc
C)copper
D)cobalt
E)nickel

Question 36

The coordination theory was proposed by:

A)Bailar
B)Jorgensen
C)Blomstrand
D)Werner
E)none of these

Question 37

True or false: Transition metals show great similarities both within a given period and within a given vertical group.

Question 38

Which metal is most widely used in the electrical systems of homes and factories?

A)copper
B)silver
C)gold
D)tungsten
E)titanium

Question 39

Metals usually have higher melting points than nonmetals.

Question 40

What transition metal is used in stainless steel?

A)nickel
B)titanium
C)chromium
D)iridium
E)niobium

Question 41

Because they have the same atoms,bonds,and formulas,geometrical isomers have the same color.

Question 42

In which of the following complexes does the transition metal have a d⁸ configuration?

A)PtCl₄^2-
B)Cu(H₂O)₆²⁺
C)Ni(CO)₄
D)Zn(NH₃)₄²⁺
E)Fe(CN)₆^3-

Question 43

What is the formula for the hexaaquachromium(II)ion?

A)[Cr(H₂O)₆]²⁺
B)[Cr₂(H₂O)₆]⁴⁺
C)[Cr(H₂O)₄]²⁺
D)[Cr₂(H₂O)₆]²⁺
E)[Cr(H₂O)₆]^4-

Question 44

Suppose you are studying coordination compounds of Co(II)with the ligand pyridine (py,C₅H₅N,molar mass = 79.10).You isolate a crystalline compound,and since the only available anions are Cl^- and NO₃^-,you hypothesize the empirical formula of the coordination compound must be Co_w(py)_x(Cl)_y(NO₃)_z.
You analyze for pyridine (K_b is approximately 10^-9)by dissolving 0.1000 g of complex in 10 mL of H₂O and titrating with a 0.01 M HCl solution.Which of the following indicators should be used to detect the endpoint? (Assume that the initial concentration of pyridine is approximately 0.01 M. )

A)bromophenol blue,pH range of color change = 3.0-4.6
B)methyl red,pH range of color change = 4.8-6.0
C)bromothymol blue,pH range of color change = 6.0-7.6
D)thymol blue,pH range of color change = 8.0 -9.6
E)alizarin yellow,pH range of color change = 10.1-12.0

Question 45

Ethylenediamine (en)is a bidentate ligand.What is the coordination number of cobalt in [Co(en)₂Cl₂]Cl?

A)four
B)five
C)seven
D)eight
E)six

Question 46

When 6.3 moles of [Co(NH₃)₅Cl]Cl₂ is dissolved in water,how many moles of ions are in solution?

A)3.3
B)4.3
C)2.1
D)19
E)57

Question 47

Analysis of the data from a titration indicates that a 0.1190-g sample of the complex contains 0.0844 g of py.Further analysis shows that 0.1190 g of the complex contains a 0.0157 g of cobalt and 0.0189 g of chloride.What is the empirical formula of the complex?

A)Co(py)₆(Cl)(NO₃)
B)Co(py)₄Cl₂
C)Co₂(py)₅(Cl)₂(NO₃)₂
D)Co₃(py)₈(Cl)₂(NO₃)₄
E)Co(py)₄(NO₃)₂

Question 48

Which of the following coordination compounds will form a precipitate when treated with an aqueous solution of AgNO₃?

A)[Cr(NH₃)₃Cl₃]
B)[Cr(NH₃)₆]Cl₃
C)[Cr(NH₃)Cl]NO₃
D)Na₃[Cr(CN)₆]
E)Na₃[CrCl₆]

Question 49

Which of the following complexes can exhibit optical isomerism? (en = H₂N-CH₂-CH₂-NH₂ and is bidentate)

A)cis-Co(NH₃)₄Cl₂
B)trans-Co(en)₂Br₂
C)cis-Co(en)₂Cl₂
D)Co(NH₃)₃Cl₃
E)none of these

Question 50

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

A)diaquatetrachloroaurate(0)ion
B)diaquatetrachloroaurate(III)ion
C)diaquatetrachloroaurate(I)ion
D)diaquatetrachlorogold(III)ion
E)diaquatetrachlorogold(I)ion

Question 51

The coordination theory was proposed by Alfred Packer.

Question 52

What is the sum of all isomers (geometrical and optical)that the complex ion Co(en)₂Cl₂⁺ exhibits?

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

Question 53

Consider the following complexes:
I.Pt(NH₃)₂Cl₂
(square planar)
II.Rh(en)₃²⁺
(en = H₂N-CH₂-CH₂-NH₂ and is bidentate)
III.CoCl₄^2-
(tetrahedral)
Which can exhibit cis-trans isomerism?

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

Question 54

A coordination compound of Cu²⁺ can be described as Cu(NH₃)_xSO₄ and is known to contain 29.92% NH₃ by mass.The value of x is:

A)2
B)3
C)4
D)6
E)none of these

Question 55

Suppose you are studying coordination compounds of Co(II)with the ligand pyridine (py,C₅H₅N,molar mass = 79.10).You isolate a crystalline compound,and since the only available anions are Cl^- and NO₃^-,you hypothesize the empirical formula of the coordination compound must be Co_w(py)_x(Cl)_y(NO₃)_z.
You discover that the complex decomposes in water.You dissolve 0.1000 g of the complex in H₂O and add excess NaHg(SCN)₄,which precipitates Co(II)as CoHg(SCN)₄(s).After the precipitate is washed and dried,its mass is 0.1102 g.How many grams of cobalt are contained in 0.1000 g of the complex?

A)0.1102
B)0.0396
C)0.0132
D)0.437
E)0.0548

Question 56

What is the correct formula for sodium tetrachlorocuprate(II)?

A)Na₂(CuCl₆)
B)Na₄(CuCl₄)
C)Na(CuCl₄)
D)Na₂(CuCl₄)
E)Na₃(CuCl₄)

Question 57

The empirical formula of a compound with a mass percent composition of 6.78% H,31.43% N,39.76% Cl,and 22.03% Co is consistent with which of the following complexes?

A)[Co(NH₃)₃Cl₃]
B)[Co(NH₃)₄Cl₂]Cl
C)[Co(NH₃)₅Cl]Cl₂
D)[Co(NH₃)₆]Cl₃
E)none of these

Question 58

Which of the following complexes shows geometrical isomerism?

A)[Co(NH₃)₅Cl]SO₄
B)[Co(NH₃)₆]Cl₃
C)[Co(NH₃)₅Cl]Cl₂
D)K[Co(NH₃)₂Cl₄]
E)none of these

Question 59

Addition of AgNO₃ to aqueous solutions of the complex results in a cloudy white precipitate,presumably AgCl.You dissolve 0.1000 g of the complex in H₂O and perform a precipitation titration with 0.0500 M AgNO₃ as the titrant.Using an electrode that is sensitive to [Ag⁺],you reach the endpoint after 9.00 mL of titrant are added.How many grams of chloride ion were present in the 0.1000-g sample?

A)4.50 $\times$ 10^-4
B)5.00 $\times$ 10^-3
C)1.77 $\times$ 10^-3
D)6.38 $\times$ 10^-2
E)1.60 $\times$ 10^-2

Question 60

What is the formula for the pentaamminehydroxocopper(II)ion?

A)[Cu(NH₃)(OH)₅]^3-
B)[Cu(NH₃)₅(OH)₅]²⁺
C)[Cu(NH₃)₅(OH)]²⁺
D)[Cu(NH₃)₅(OH)₅]^3-
E)[Cu(NH₃)₅(OH)]⁺

Question 61

The complex FeL₆²⁺,where L is a neutral ligand,is known to be diamagnetic.The number of d electrons in this complex ion is:

A)4
B)5
C)6
D)7
E)8

Question 62

NiCl₄^2- (tetrahedral)

A)0
B)1
C)2
D)4
E)5

Question 63

The complex ions of Zn²⁺ are all colorless.The most likely explanation for this is:

A)Zn²⁺ is paramagnetic.
B)Zn²⁺ exhibits "d orbital" splittings in its complexes such that they absorb all wavelengths in the visible region.
C)Since Zn²⁺ is a d¹⁰ ion,it does not absorb visible light even though the "d orbital" splittings are correct for absorbing visible wavelengths.
D)Zn²⁺ is not a transition metal ion.
E)None of these is correct.

Question 64

CoF₆^3- (weak field)

A)0
B)1
C)2
D)4
E)5

Question 65

The ____ isomer of the complex Ni(en)₂Cl₂ exhibits optical isomers,but the _____ isomer does not.

A)cis,trans
B)trans,cis
C)Both isomers exhibit optical isomers.
D)Neither isomers exhibit optical isomers.
E)Depends on the wavelength of plane-polarized light used.

Question 66

The geometry of a coordination compound with a coordination number of 4 is

A)tetrahedral,in order to minimize repulsions between the ligands
B)octahedral,since there are two different positions possible for each ligand
C)square planar,to allow room for the counterion because the ligands take up so much space
D)linear,since there are two ligands on each side of the transition metal
E)tetrahedral or square planar,but too difficult to predict based on the information given

Question 67

How many of the following compounds exhibit geometric isomers?
I.Pt(NH₃)₂Cl₂ (square planar)
II.[Co(H₂O)₂]Cl₃
III.Ni(NH₃)₄(NO₂)₂
IV.K₂[CoCl₄]

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

Question 68

Copper(I)complexes would be expected to be colorless.

Question 69

Which complex ion shape is not capable of showing cis-trans isomerism?

A)octahedral
B)square planar
C)tetrahedral
D)two of these
E)none of these

Question 70

Which of the following statements is true about the octahedral complexes of Ni²⁺?

A)Both strong- and weak-field complexes are diamagnetic.
B)The strong-field complex is diamagnetic and the weak-field complex is paramagnetic.
C)The strong-field complex is paramagnetic and the weak-field complex is diamagnetic.
D)Both strong- and weak-field complexes are paramagnetic.
E)There are no octahedral complexes of Ni.

Question 71

Which of the following statements concerning the complex ion Co(en)₂Cl₂⁺ is true? (en = ethylenediamine,NH₂CH₂CH₂NH₂)?

A)The complex ion contains Co(I).
B)The complex ion exhibits cis and trans geometrical isomers,but no optical isomers.
C)The complex ion exhibits two geometrical isomers (cis and trans)and two optical isomers.
D)Since en is a strong field ligand (large $\Delta$ ),the complex ion is paramagnetic.
E)The geometric isomers of the complex ion have identical chemical properties.

Question 72

Which of the following is true about coordination complexes?

A)The metal is a Lewis base and the ligands are Lewis acids.
B)Only complexes with coordination number six are found in nature.
C)When the ligands approach a transition metal ion in an octahedral field,the d_xz,d_yz,and d_xy atomic orbitals are affected the least by the ligands.
D)None of the above is true.
E)All of the above are true.

Question 73

Calculate the total number of unpaired electrons in the following complex ions: Zn(OH₂)₆²⁺,Ni(CN)₄^2- (square planar),Co(NH₃)₆³⁺ (strong field).

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

Question 74

For the process Co(NH₃)₅Cl²⁺ + Cl^- $\to$ Co(NH₃)₄Cl₂⁺ + NH₃ what would be the ratio of cis to trans isomer in the product?

A)1 : 1
B)1 : 2
C)1 : 4
D)4 : 1
E)2 : 1

Question 75

CuCl₂^- (linear)

A)0
B)1
C)2
D)4
E)5

Question 76

Which of the following is paramagnetic?

A)Zn(H₂O)₆²⁺
B)Co(NH₃)₆³⁺ (strong field)
C)Cu(CN)₃^2-
D)Mn(CN)₆^2- (strong field)
E)none of these

Question 77

Give the number of geometrical isomers for the octahedral compound [MA₂B₂C₂],where A,B,and C represent ligands.

A)1
B)2
C)3
D)5
E)none of these

Question 78

Which of the following are structural isomers?
I.coordination isomers
II.linkage isomers
III.geometrical isomers
IV.optical isomers

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

Question 79

Ni(NH₃) ₆²⁺

A)0
B)1
C)2
D)4
E)5

Question 80

Which of the following ligands might give linkage isomers?

A)NO₂^-
B)SCN^-
C)H₂NHC₂CH₂NH₂
D)A and B
E)A,B,and C