Which of the following metals produces hydrogen gas when heated with hot concentrated alkali?

Consider the reaction:
$KOH + O_3 \to$ coloured solid $(a) +$ Gas $(b) + H_2O$
Select the $CORRECT$ statement.

What type of oxides do alkali metals form? Discuss some of the physical properties of these oxides.

$A$ $s$-block element $(M)$ reacts with oxygen to form an oxide of the formula $MO_{2}$. The oxide is pale yellow in colour and paramagnetic. The element $(M)$ is:

Match the following:

Metal	Ore
$1$. Sodium	$a$. Barite
$2$. Potassium	$b$. Carnallite
$3$. Barium	$c$. Beryl
$4$. Beryllium	$d$. Chile saltpetre

The useful by-products obtained in the $Solvay$ process of manufacturing sodium carbonate are: