When ammonium dichromate is heated,the gas formed is

Which of the following is a non-combustible hydride?

$A$ obtained by Ostwald's method involving air oxidation of $NH_3$,upon further air oxidation produces $B$. $B$ on hydration forms an oxoacid of Nitrogen along with evolution of $A$. The oxoacid also produces $A$ and gives positive brown ring test.

With reference to protonic acids,which of the following statements is correct?

What are the boiling points of nitrogen and oxygen gases?

$N_2O_3$ is a/an.......