Deck 21: Coordination Chemistry: Reactions of Complexes

Question 1

In terms of reaction rates, what do complexes of majority of s block metals and complexes of M³⁺ ions of the f block have in common?

A) They are both non-labile.
B) They are both very labile.
C) They have nothing in common.

Answer 1

B

Question 2

Which mechanism takes place in one step only?

A) associative
B) dissociative
C) interchange

Answer 2

C

Question 3

What is rate-determining step?

A) It is the slowest elementary step that dominates the rate law and speed of the reaction.
B) It is the first step in the mechanism that determines the direction of reaction.
C) It is any step that leads to an unstable reaction intermediate.

Answer 3

B

Question 4

Which of the following three Pt complexes is going to have the fastest substitution of Cl ligand?

A) trans-[PtCl(H)(PEt₃)₂]
B) trans-[PtCl(CH₃)(PEt₃)₂]
C) trans-[PtCl(OH)(PEt₃)₂]

Question 5

Steric strain (i.e. the presence of bulky ligands) in octahedral complexes favours __________ rate-determining step.

A) associative
B) dissociative
C) interchange.

Question 6

Which of the following ligands should enable base-accelerated ligand substitution?

A) bipyridyl
B) acetylacetonato
C) ethylenediamine

Question 7

Identify the correct statement:

A) If the reaction intermediate has square pyramidal geometry, the reaction proceeds with the retention of the initial geometry.
B) If the reaction intermediate has trigonal bipyramidal geometry, the reaction proceeds with the retention of the initial geometry.
C) If the reaction intermediate has square planar geometry, the reaction proceeds with the retention of the initial geometry.

Question 8

Identify the mechanism that is not applicable to the isomerisation of octahedral complexes.

A) Bailard twist mechanism
B) Berry pseudorotation mechanism
C) Ray-Dutt twist mechanism.

Question 9

Which of the following elementary steps is not part of the outer sphere electron transfer mechanism?

A) association
B) bridge formation
C) diffusion.

Question 10

Identify the correct statement:

A) Square planar complexes react following the associative mechanism unless steric effects prevent association.
B) The trans effect plays no role for ligand substitution in octahedral complexes.
C) The rate-determining step in inner sphere electron transfer is very frequently the bridge formation step.