The energy required to separate the ion pair =
I have assumed a copper(II) ion and an electrostatic model.
For 2 charges
The work done in separating the 2 charges from
I will assume a wholly electrostatic model where we have discrete ions in contact.
The ionic radii are:
This means the total distance between the centre of the 2 ions is:
The electronic charge =
So the charge on the
The charge on the
Putting these values into