Benniston L2

Question 1

What doe the volume of activation help you determine

Answer 1

The volume of activation is measured by looking at the effect of pressure on reaction rate

Question 2

Describe the graph we can plot to help us calculate volume of activation

Answer 2

A graph of ln (k/kp=0) vs P should be a straight line with a slope =- ∆V‡/RT.
So to calculate ∆V we times -RT by the gradients

Question 3

What is lability

Answer 3

Lability is the ability of a complex to engage in reaction that result in replacing one or more ligands by others

Question 4

Define labile

Answer 4

Complexes which rapidly engages in reactions that replaces one or more ligands

Question 5

Define inert

Answer 5

Complexes which slowly or do not engage in reactions that replaces one or more ligands

Question 6

Describe labile in terms of taube classification

Answer 6

Labile metal ions have either an empty low energy t2g orbital, or at least one electron in a high-energy eg orbital

Question 7

Describe inert metal ions in terms of taube classification

Answer 7

Inert metal ions will have at least one electron in each t2g orbital and no electrons in eg orbitals

Question 8

What is crystal field activation energy and how do we calculate it

Answer 8

Energies of valence d orbital calculated for various idea geometries of possible transition states for substitution reactions. Crystal field stabilisation energy calculated for ground state and transition state and difference defined as the crystal field activation energy

Question 9

How do we interpret crystal field activation energy

Answer 9

Negative CFAE - transition state more stable, reaction easier, labile complex
Positive CFAE - transition state less stable, reaction harder, inert

Question 10

What d complexes are the most inert

Answer 10

d3 and d8

Question 11

What complexes are the most labile

Answer 11

d4 and d9