Metaphosphoric acid has the formula

Phosphine is prepared by the reaction of $P_4$ with which of the following?

In the ring test of $NO_{3}^{-}$ ion,$Fe^{2+}$ ion reduces nitrate ion to nitric oxide,which combines with $Fe^{2+}_{(aq)}$ ion to form a brown complex. Write the reactions involved in the formation of the brown ring.

Which of the following is obtained by catalytic oxidation of ammonia?

When white phosphorus is boiled with a caustic soda solution,it yields $................$.

The number of pentagons in $C_{60}$ and trigons (triangles) in white phosphorus,respectively,are