Match the constituents of cements with their percentage proportion :

Constituents	Percentage
$1$. $CaO$	$a$. $2-3\%$
$2$. $MgO$	$b$. $50-60\%$
$3$. $SiO_2$	$c$. $5-10\%$
$4$. $Al_2O_3$	$d$. $20-25\%$

$A$ white solid '$A$' on heating produces a gas that turns lime water milky,and the remaining solid residue is yellow when hot but turns white on cooling. The solid '$A$' is:

Give the correct order of initials $T$ or $F$ for following statements. Use $T$ if statement is true and $F$ if it is false.
$(I)$ Number of $S-S$ bonds in $H_{2}S_{n}O_{6}$ is $(n - 1)$.
$(II)$ When $F_{2}$ reacts with water,it gives $HF, O_{2}$ and $O_{3}$.
$(III)$ $LiNO_{3}$ and $BaCl_{2}$ compounds are used in fireworks.
$(IV)$ $Be$ and $Mg$ hydrides are ionic and polymeric.

Which elements are present in the $s$-block?

Match the following items in Column-$I$ with the corresponding items in Column-$II$.

Column-$I$	Column-$II$
$I$. $Na_2CO_3 \cdot 10H_2O$	$A$. Portland cement ingredient
$II$. $Mg(HCO_3)_2$	$B$. Castner-Kellner process
$III$. $NaOH$	$C$. Solvay process
$IV$. $Ca_3Al_2O_6$	$D$. Temporary hardness

Match the following substances in List-$I$ with their uses in List-$II$:
| List-$I$ (Substance) | List-$II$ (Use) |
| :--- | :--- |
| $(A)$ $Na_2O_2$ | $(I)$ Photoelectric cells |
| $(B)$ $D_2O$ | $(II)$ Antacid |
| $(C)$ $Cs$ | $(III)$ Oxidising agent |
| $(D)$ $Mg(OH)_2$ | $(IV)$ Moderator |