Paragraph-1
Upon heating $\mathrm{KClO}_3$ in the presence of catalytic amount of $\mathrm{MnO}_2$, a gas W is formed. Excess amount of $W$ reacts with white phosphorus to give $X$. The reaction of $X$ with pure $\mathrm{HNO}_3$ gives $Y$ and $Z$.
Y and Z are, respectively :