Cu Ag Redox Reaction?

Question

Having a little bit of trouble... In the redox reaction using Cu and Ag

Cu (0) -----> Cu (2+)

2Ag + + 2e- ------> 2Ag (0)

I do not understand how you get the +2 charge on Cu

Answer 1

Cu(0) ---> Cu(+2) + 2 e(-1)

The charge +2 cames from the fact that Cu(0) lost 2 electrons.

Answer 2

In order to understand why Cu gains a plus two charge as a cation, you need to understand the way it loses electrons.

Cu has one electron in the 4s orbital and 10 in the 3d orbital. When it is oxidized to the +2 state, it loses the one electron in the s orbital and one electron from the d orbital. This gives it a plus two charge, or two more protrons than electrons, with the loss of the two electrons.

In order to understand transitional metal cations you need to be aware of their s and d orbital electrons.

Usually you don't need to ask this sort of question when you are doing redox equations. You are told what charge the cations and anions have or get and you just balance the silly things.

But it is good that you are asking questions beyond the scope of the current topic. But you must have skipped over the chapter on cations and anion formation for transitional metals, which should be covered at an earlier time than redox reactions.

Answer 3

the +2 charge on Cu indicates that on oxidation Cu has lost 2 electrons and hence Cu is reduced to Cu(2+) in the above reaction.

Answer 4

Cu-->cu2+ +2e-