The property used in the industrial preparation of nitrogen and oxygen from air is?

The oxidation of ammonia in excess air produces?

One of the products of the thermal decomposition of sodium trioxonitrate (V) is?

To a solution of an unknown compound, a little dilute tetraoxosulphate (VI) acid was added with some freshly prepared iron (II) tetraoxosulphate (VI) solution. The brown ring observed after the addition of a stream of concentrated tetraoxosulphate (VI) acid confirmed the presence of?

In the above set up substances X and Y are respectively