Nitrogen forms how many oxides?

$P_2O_3 + H_2O \rightarrow X$
$Red \ P_4 + \text{alkali} \rightarrow Y$
$X$ and $Y$ are oxoacids of phosphorus. The number of $P-OH$ bonds in $X$ and $Y$ respectively is:

Of the following hydrides,which has the lowest boiling point?

Write a note on allotropes of phosphorus.

Which of the following metals produces nitrous oxide $(N_2O)$ when reacted with dilute $HNO_3$?

Which of the following compounds does not produce ammonia upon heating?