Match the average fundamental compounds with their proper percentage present in Portland cement.

Compound	Percentage proportion
$1. CaO$	$d. 50-60\%$
$2. Al_2O_3$	$a. 5-10\%$
$3. SO_3$	$b. 1-3\%$

$A$ hydrated solid $X$ on heating initially gives a monohydrated compound $Y$. $Y$ upon heating above $373 \ K$ leads to an anhydrous white powder $Z$. $X$ and $Z$,respectively,are

Nitrolim is

Which of the following pairs of atomic numbers represents elements belonging to the $s$-block?

Present a comparative account of the alkali and alkaline earth metals with respect to the following characteristics :
$(a)$ Tendency to form ionic/covalent compounds.
$(b)$ Nature of oxides and their solubility in water.
$(c)$ Formation of oxosalts.
$(d)$ Solubility of oxosalts.
$(e)$ Thermal stability of oxosalts.

Match List-$I$ with List-$II$ :

List-$I$ (Elements)	List-$II$ (Properties)
$(a)$ $Ba$	$(i)$ Organic solvent soluble compounds
$(b)$ $Ca$	$(ii)$ Outer electronic configuration $6s^2$
$(c)$ $Li$	$(iii)$ Oxalate insoluble in water
$(d)$ $Na$	$(iv)$ Formation of very strong monoacidic base

Choose the correct answer from the options given below :