The valence shell electronic configuration of alkali metals is

Which of the following has the lowest melting point?

$NaHCO_3$ can be manufactured by Solvay's process but $K_2CO_3$ cannot be prepared because

Identify the compound which gives $CO_2$ more readily on heating.

Which of the following reactions is not involved in the Solvay process?

Given below are two statements:
Statement $I$: The chlorides of $Be$ and $Al$ have $Cl^{-}$-bridged structure. Both are soluble in organic solvents and act as Lewis acids.
Statement $II$: Hydroxides of $Be$ and $Al$ dissolve in excess alkali to give beryllate and aluminate ions.
In the light of the above statements,choose the correct answer from the options given below.