Can anyone please describe a chemical test for ammonia..?
Forget the ninhydrin! The usual chemical test for ammonia is to hold a piece of filter paper dipped in concentrated hydrochloric acid at the mouth of the tube. You’ll see dense white fumes [smoke] caused by the ammonium chloride formed. If you want to test for copper compounds the flame test is fine, but you can also add ammonia solution to a solution of the copper compound which then turnd an intense royal blue [due to [Cu(NH3)4]2+ ions.