Mechanisms of Redox reactions

Question 1

What are the two brad classes REDOX mechanisms can be divided into?

Answer 1

1) Inner Sphere mechanism
2) Outer Sphere mechanism

Question 2

What is the definition of an inner sphere mechanism?

Answer 2

A mechanism in which the reductant and oxidant share a ligand in their inner (or primary) coordination sphere with the electron being transferred across the bridging group.

Question 3

What is the definition of an outer sphere mechanism?

Answer 3

A mechanism involving electron transfer from the reductant to the oxidant with the co-ordition spheres of both remaining intact i.e. the electron simply “hops” from reductant to oxidant.

Question 4

In a REDOX reaction what does a change in eg* occupancy lead to?

Answer 4

A much slower rate

• due to high activation energy for electron transfer