On heating anhydrous $Na_2CO_3$,........ is evolved.

Nitrolim is

Match the following compounds in Column-$I$ with their products of heating effect in Column-$II$:

Column-$I$ (Compound)	Column-$II$ (Products of heating effect)
$a$. $LiNO_3$	$P$. Metal oxide
$b$. $FeSO_4 \cdot 7H_2O$	$Q$. Paramagnetic gas
$c$. $NaHCO_3$	$R$. Acidic gas
$d$. $BeCO_3$	$S$. Evolved gas has same number of $\sigma$ and $\pi$ bonds

$A$ mixture of sodium oxide and calcium oxide is dissolved in water and saturated with excess carbon dioxide gas. The resulting solution is ...... It contains ......... :

Write a note on $s$-block elements of the periodic table.

Zeolites are