Which of the following represents laughing gas?

On heating,lead$(II)$ nitrate gives a brown gas $(A).$ The gas $(A)$ on cooling changes to a colourless solid/liquid $(B).$ $(B)$ on heating with $NO$ changes to a blue solid $(C).$ The oxidation number of nitrogen in solid $(C)$ is :

Which of the following is one of the products obtained when calcined phosphate rock is reduced with coke and sand in an electric furnace at $1773 \ K$?

Red phosphorus can be obtained from white phosphorus by:

In which of the following reactions is there no liberation of nitrogen gas?

The most stable hydride is