What is released when washing soda is heated?

Which chloride does not exist as hydrate?

When magnesium burns in air,the compounds of magnesium formed are magnesium oxide and

Which of the nitrates on strong heating leaves the metal as the residue?

The highly reactive alkali metals are kept in

Assertion $(A)$: Alkali metals and their salts impart characteristic flame colours.
Reason $(R)$: Alkali metals have low ionization enthalpy values. So, electron excitation is possible.
The correct option among the following is