Which of the following combinations will produce $H_2$ gas?

$NaNO_3$ on heating gives which gas?

Which of the following statements is incorrect?

Consider the following statements.
$I$. $Cs^{+}$ ion is more highly hydrated than other alkali metal ions.
$II$. Among the alkali metals,only lithium forms a stable nitride by direct combination with nitrogen.
$III$. Among the alkali metals $Li, Na, K, Rb$,the metal $Rb$ has the highest melting point.
$IV$. Among the alkali metals $Li, Na, K, Rb$,only $Li$ forms peroxide when heated with oxygen.
Select the correct statement.

On heating quick lime with coke in an electric furnace,we get

The oxide of an element whose electronic configuration is $1s^{2} 2s^{2} 2p^{6} 3s^{1}$ is