Alkali metals lose electrons from which orbitals?

Identify the element forming peroxide on reaction with oxygen.

Provide the names,symbols,and electronic configurations of the elements in the $1^{st}$ group.

Which alkali metal during flame test will show color corresponding to maximum wavelength?

When substance $A$ reacts with water,it produces a combustible gas $B$ and a solution of substance $C$ in water. When another substance $D$ reacts with solution $C$,it produces the same gas $B$,even when reacting with dilute sulfuric acid at room temperature. $A$ gives a golden yellow flame in a Bunsen burner flame. What are $A, B, C,$ and $D$ respectively?

Sodium peroxide is used to purify the air in submarines and confined spaces because