How do you test ammonia gas?

13 What property of hydrogen is observed in the following experiments?
i) Balloon, filled with hydrogen, floats.
ii) Pop sound is heard when a burning splint is introduced at the mouth of hydrogen filled jar.
iii) When black cupric oxide is heated in a stream of hydrogen, reddish colour is obtained. 14 Select the non-metals amongst the following 
i) Bismuth   ii) Sulphur   iii) Arsenic   iv) Hydrogen. 16 Write chemical equations for reactions taking place when
i) Cinnabar is heated in air.
ii) Concentrated sulphuric acid and sulphur are heated together. Calcium metal reacts with water. 17 What are the uses of ammonia?