White phosphorus when boiled with a strong solution of caustic soda produces:

In the brown ring test,the brown colour of the ring is due to

Which among the following group-$15$ elements does $NOT$ react with concentrated sulphuric acid?

Name three oxoacids of nitrogen. Write the disproportionation reaction of that oxoacid of nitrogen in which nitrogen is in $(+3)$ oxidation state.

Ammonia is not produced in the reaction of

On mixing two colourless gases,a deep brown colour is observed. The gases are