Which of the following methods is generally used for the extraction of alkali metals?

Starting with sodium chloride,how would you proceed to prepare:
$(i)$ sodium metal
$(ii)$ sodium hydroxide
$(iii)$ sodium peroxide
$(iv)$ sodium carbonate?

$A$ metal $M$ reacts with $N_2$ to form a compound $A$ $(M_3N)$. Heating $A$ at high temperature gives back $M$,and passing $A$ through $H_2O$ produces gas $B$. Gas $B$ turns $CuSO_4$ solution into a deep blue color. What are $A$ and $B$?

What is the formula of calcium cyanamide?

What else is present in a fire extinguisher along with ${H_2}SO_4$?

Which metal is not silvery white?