[iScience]

EDIT: i decided to just rewrite the whole question..

i have brass metal in contact with ammonia(liq), could  someone help me identify the oxidation reaction?

i thought the oxidation rxn was supposed to involve the ammonia and the copper, but that combination would lead to the copper being reduced, not oxidized. am i right?
how exactly is copper losing its electrons?

[Borek]

Why do you think copper gets oxidized?

[unsu]

i thought the oxidation rxn was supposed to involve the ammonia and the copper, but that combination would lead to the copper being reduced, not oxidized. am i right?

sorry I do not understand anything you are talking about 

[thelastone]

I think to recall that anhydrous ammonia doesn't react with Copper or Zinc alone, BUT when there's humidity forms a very stable ammonia complex (Cu(NH₃)₆)²⁺.

Hope it helps.

[john13579]

The copper is indeed oxidized to copper(II).
Copper reacts readily with aqueous ammonia in the presence of oxygen, as follows:
Cu+ 1/2 O2 + 4NH3(aq)  Cu(NH3)4²⁺ + 2 OH-

The reaction only works in presence of oxygen as the oxidizing agent (http://jes.ecsdl.org/content/100/10/421.short)

ammonia serves to form the Tetraamminecopper(II)  ion and remove the protective oxide layer form the surface of the metal allowing for further oxidation.

It is referred to as season cracking (http://en.wikipedia.org/wiki/Season_cracking)