Valency electrons in alkali metals are

Identify $A$ to $E$ in the following reactions:
$\underset{\text{Alkali metals}}{\mathop{A}}\,+N_2$ $\xrightarrow{\Delta }B$ $\xrightarrow{H_2O}C+D$
$C+HCl\rightarrow E$
(Where $D$ is $NH_3$ and $E$ is a salt,and $C$ is a base)

What is the correct order of ionic mobility for alkali metal ions in an aqueous medium?

How is magnesium obtained from the following?

Which of the following gives a green colour to flame?

Identify the basic oxide from the following.