When sodium $(Na)$ metal is dissolved in liquid ammonia $(NH_3)$, it imparts a blue colour to the solution. This blue coloration is due to:

Sodium carbonate is manufactured by the Solvay process. The products that are recycled are:

Magnesium burns in air to give

What is lye?

Which of the following alkali metals has the least melting point?

State True or False:
$(1)$ Half-life of $^{223}Fr$ is $21 \ s$.
$(2)$ $Li^{+}$ has a high hydration enthalpy and therefore its salts are usually hydrated in nature.
$(3)$ Among all the alkali metals,only $Na$ can react with nitrogen of air and form a nitride.
$(4)$ Except $LiF$,other halides of $Li$ are soluble in water.