Transition Metals

Question 1

A solution appears blue. Blue light has a higher frequency than red light.
Suggest whether the energy change will be bigger, smaller, or same for a transition metal ion that forms a red solution. (2)

Answer 1

Greater
Frequency of blue light is greater than red light resulting in ‘f’ to be greater resulting in energy needed to jump subshell being larger

Question 2

State three different features of transition metal complexes that cause a change in the value of E, the energy change between the ground state and the excited state of the d electrons (3)

Answer 2

Central metal ion
Oxidation states
Ligand

Question 3

Give electron configuration of Zn2+ ion.

Use your answer to explain why this ion is not classified as a transition metal ion (2)

Answer 3

[Ar] 3d10

It has a full d shell so no electron can jump subshell

Question 4

In terms of bonding, explain the meaning of the term complex (2)

Answer 4

A central metal ion being coordinate lay bonded by one or more ligand

Question 5

State the meaning of the term homologous (1)

Answer 5

In the same state

Question 6

Suggest why ions from s block elements do not usually act as catalysts (1)

Answer 6

Do not have variable oxidation states

Question 7

Give one reason why impurities in the reactants can cause problems in processes that use heterogeneous catalysts (1)

Answer 7

They block the active sites so that the reactants cannot be adsorbed onto the surface of the catalyst

Question 8

Give the meanings of the term autocatalysed (1)

Answer 8

A catalyst that is found in the products of the equation

Question 9

Explain the meaning of the meaning of the terms ligand and bidentate as applied to transition metal complexes (2)

Answer 9

Ligand Is a molecule that forms a coordinate bond with a central metal ion
A bidentate ligand forms two coordinate bonds to the central metal ion

Question 10

The complex ion formed in aqueous solution between cobalt (II) ions and chloride ions is a different colour from the [Co(H2O)6]2+ ion.
Explain why these complex ions have different colours (3)

Answer 10

They have different frequency of light absorbed
So there is a different energy needed to jump subshells
In different complexes the d orbital will be different

Question 11

Explain why electron transition causes a solution containing the transition metal ion to be coloured. (2)

Answer 11

One coloured Light is absorbed

Remaining colour/ frequency/ wavelength is transmitted