Deck 28: D-Block Chemistry

Question 1

What is the electronic configuration of Cr³⁺?

A) [Ar] 3d² 4s¹
B) [Ar] 3d³
C) [Ar] 3d¹ 4s²
D) [Ar] 3d⁵

Answer 1

B

Question 2

Which of the following are common oxidation states of Mn? Please select all that apply.

A) 5+
B) 4+
C) 7+
D) 2+

Answer 2

B, C, D

Question 3

Scandium is one of the few transition elements to show a single oxidation state in its compounds where it occurs as a __ ion.

Answer 3

3+

Question 4

Moving from left to right across the Periodic Table, the atomic radii of the first row transition elements does not show the same trend as the s and p blocks, e.g. from lithium to fluorine. Why?

A) d electrons screen more effectively than s and p electrons, so Z_eff falls.
B) The increase in the electron-electron repulsion becomes more important as the d orbitals are filled and counteracts the effect of the increase in Z_eff.
C) d electrons screen less effectively than s and p electrons, so Z_eff rises.
D) Z_eff is unaffected by the increasing number of electrons as d electrons screen so poorly.

Question 5

The change in the third ionization energy does not vary smoothly across the first transition series. Why? Please select all that apply.

A) A paired electron is lost when iron is oxidised from 2+ to 3+
B) Iron gains an electron which must be paired.
C) Manganese loses an unpaired electron when it is oxidised from 2+ to 3+.
D) Manganese gains an electron which must be paired.

Question 6

Although a number of copper(I) compounds exist, CuF is unknown

Question 7

Match the denticity to the ligand.
-H₂NCH₂NHCH₂NH₂

A) tridentate
B) bidentate
C) monodentate
D) hexadentate

Question 8

Match the denticity to the ligand.
-C₂O₄^2-

A) tridentate
B) bidentate
C) monodentate
D) hexadentate

Question 9

Match the denticity to the ligand.
-Water

A) tridentate
B) bidentate
C) monodentate
D) hexadentate

Question 10

Match the denticity to the ligand.
-EDTA^4-

A) tridentate
B) bidentate
C) monodentate
D) hexadentate

Question 11

The pH of a solution could affect the ability of EDTA to act as a hexadentate ligand.

Question 12

The polydentate ligand, 2,2-bipyridine can form a chelate ring with a metal atom. How many members does the chelate ring have?

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

Question 13

The name of the coordination compound K₄[Fe(CN)₆] is _________ ____________________

Question 14

The formula of the coordination compound hexaaquairon(II) sulfate is___________________________

Question 15

What is the coordination number of iron in the complex [Fe(en)₂Cl₂] ?

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

Question 16

The compound with the formula [CoCl(H₂O)₅]Cl₂ can exhibit which of the following types of isomerism? Please select all that apply.

A) Linkage isomerism
B) Optical isomerism
C) Structural isomerism
D) Hydration isomerism

Question 17

The compound with the formula [CoCl₂(en)₂] has three possible isomers.

Question 18

Crystal field theory predicts that the d_x²_-y² orbital is highest in energy in a square pyramid.

Question 19

Calculate the CFSE for [Mn(H₂O)₆]⁴⁺ in terms of Δ_o?

A) -0.8Δ_o
B) -0.4Δ_o
C) -1.2Δ_o
D) -1.6Δ_o

Question 20

In which of the following dⁿ configurations in an octahedral field, would the pairing energy need to be considered to predict whether the ion would be low or high spin?

A) d³
B) d⁵
C) d¹
D) d⁹

Question 21

Tetrahedral complexes are normally high spin.

Question 22

The high spin Fe⁴⁺ ion would show a Jahn-Teller distortion in an octahedral field.

Question 23

Match the metal complex with the intensity of transition observed for a solution of that complex.
-[Mn(H₂O)₆]²⁺

A) 0.01 m² mol^-1
B) 50 m² mol^-1
C) 1 m² mol^-1
D) 200 m² mol^-1

Question 24

Match the metal complex with the intensity of transition observed for a solution of that complex.
-[CoCl₄]^2-

A) 0.01 m² mol^-1
B) 50 m² mol^-1
C) 1 m² mol^-1
D) 200 m² mol^-1

Question 25

Match the metal complex with the intensity of transition observed for a solution of that complex.
-[Co(H₂O)₆]²⁺

A) 0.01 m² mol^-1
B) 50 m² mol^-1
C) 1 m² mol^-1
D) 200 m² mol^-1

Question 26

Match the metal complex with the intensity of transition observed for a solution of that complex.
-[MnO₄]^-

A) 0.01 m² mol^-1
B) 50 m² mol^-1
C) 1 m² mol^-1
D) 200 m² mol^-1

Question 27

The compound cobalt blue (CoAl₂O₄) absorbs blue light to appear blue.

Question 28

Calculate the magnetic moment expected for a compound containing a first-row transition metal with three unpaired electrons.

A) 1.73 μB
B) 3.87 μB
C) 5.92 μB
D) 4.90 μB

Question 29

The spin only magnetic moment equation cannot be used to calculate the magnetic moment for second and third row transition metals.

Question 30

The measured magnetic moment of [Ni(SCN)₄]^2- is effectively zero, while the magnetic moment of [NiCl₄]^2- approximates to 2.83 μB. Why?

A) [Ni(SCN)₄]^2- is low spin and [NiCl₄]^2- is high spin in a tetrahedral ligand field giving different numbers of unpaired electrons.
B) [Ni(SCN)₄]^2- is tetrahedral and [NiCl₄]^2- is square planar.
C) [Ni(SCN)₄]^2- is high spin and [NiCl₄]^2- low spin in a tetrahedral ligand field giving different numbers of unpaired electrons.
D) [Ni(SCN)₄]^2- is square planar and [NiCl₄]^2- is tetrahedral.

Question 31

Match the following ions with the appropriate expression for their CFSE in terms of Δ_o (crystal field splitting) and P (pairing energy).
-[Fe(H₂O)₆]⁴⁺ (low spin)

A) -1.6 Δ_o + P
B) -2.4 Δ_o + 3P
C) -0.4 Δ_o + P
D) -0.6 Δ_o

Question 32

Match the following ions with the appropriate expression for their CFSE in terms of Δ_o (crystal field splitting) and P (pairing energy).
-[Co(H₂O)₆]³⁺ (low spin)

A) -1.6 Δ_o + P
B) -2.4 Δ_o + 3P
C) -0.4 Δ_o + P
D) -0.6 Δ_o

Question 33

Match the following ions with the appropriate expression for their CFSE in terms of Δ_o (crystal field splitting) and P (pairing energy).
-[Co(H₂O)₆]³⁺ (high spin)

A) -1.6 Δ_o + P
B) -2.4 Δ_o + 3P
C) -0.4 Δ_o + P
D) -0.6 Δ_o

Question 34

Match the following ions with the appropriate expression for their CFSE in terms of Δ_o (crystal field splitting) and P (pairing energy).
-[Fe(H₂O)₆]⁴⁺(high spin)

A) -1.6 Δ_o + P
B) -2.4 Δ_o + 3P
C) -0.4 Δ_o + P
D) -0.6 Δ_o