Reaction between Cu2+ and NH3?

Question

Can anyone show me the equation of the reaction between Cu2+ and NH3? No need to be balanced.

Thanks to those who answered seriously.

Answer 1

Cu2+ + 4NH3 → Cu[NH3]4 2+

The complex formed is called tetraamminecopper(II).

Answer 2

Dilute ammonia: you get precipitation:

Cu2+ + 2 NH3  + 2 H2O --> Cu(OH)2 + 2 NH4+

Excess ammonia: complex formation (lovely deep blue):

Cu2+ + 4 NH3 --> Cu(NH3)4 2+