Question

How many isomers are there of the complex ion [CoCl2(en)(NH3)2]+

Answer 1

I can draw three. Cl trans,NH3 cis; NH3 trans, Cl cis; Cl cis, NH3 cis. I don't see any others but check me out. Perhaps I missed one or more. "-).

Answer 2

There are four different isomers.