Name the constituents of the following alloy.:

Brass.

Name the constituents of the following alloy:

Stainless steel.

Name the constituents of the following alloy:

Bronze,

State one property in each of these alloys, which is different from its main constituents.

(i) Brass (ii) Stainless steel (ii) Bronze

A nonmetal A which is the largest constituent of air, when heated with ${\mathrm{H}}_2$ in $1:3$ ratio in the presence of a catalyst (Fe) gives a gas B. On heating with  ${\mathrm{O}}_2$ it gives an oxide C. If the oxide is passed into the water in the presence of air it gives an acid D which acts as a strong oixidsing agent. Identify A, B, C, and D.