Formation Of Coloured Ions

Question 1

What happens to TM in the dark vs in the light?

Answer 1

• in the dark, any electrons in the d-subshell occupy the lowest energy orbitals first.
• if there is space in the higher orbitals when the light shines then an electron is promoted from the lower to the higher orbitals by absorbing the fixed small amounts of energy from the light
  ^(delta)E = h x v

Question 2

What colour will the TM complex ion appear?

Answer 2

It will appear the complementary colour to the colour it absorbed.
IT WILL BE TRANSMITTED (IF SOLUTION) AND REFLECTED (IF SOLID)

Question 3

What does the colour of a TM ion depend on?

Answer 3

The size of the energy gap
Which depends on:
- the oxidation state
- the particular ligand present
- the coord no and the shape