Metal $M +$ air $\xrightarrow{\Delta } A$ $\xrightarrow{H_2O} B$ $\xrightarrow{HCl}$ White fumes; Metal $M$ can be

$A$ metal on combustion in excess air forms $X$. $X$ upon hydrolysis with water yields $H_2O_2$ and $O_2$ along with another product. The metal is

Heating a metal $X$ in nitrogen gas gives $Y$. The reaction of $Y$ with $H_2O$ produces a colorless gas. When this gas is passed through $CuSO_4$ solution,it produces a blue color. What is $Y$?

Which of the following can be used to extinguish a fire caused by sodium,potassium,and lithium?

The atomic number of an element is $11$. Its oxide will be

In which of the following is sodium metal stored?