Identify the elements of alkali metals and alkaline earth metals respectively having the highest $1^{st}$ ionization enthalpy.

Match the following compounds (Column-$I$) with their uses (Column-$II$):

Column-$I$	Column-$II$
$I. Ca(OH)_2$	$A$. Casts of statues
$II. NaCl$	$B$. White wash
$III. CaSO_4 \cdot \frac{1}{2}H_2O$	$C$. Antacid
$IV. CaCO_3$	$D$. Washing soda preparation

Which of the anhydrous salts,when it comes in contact with water,turns blue?

Match the following columns:

Column-$I$	Column-$II$
$(i)$ Solvay process	$(p)$ $Na_2O$
$(ii)$ Evolve $CO_2$ on heating	$(q)$ $Na_2O_2$
$(iii)$ Aqueous solution is not neutral towards litmus	$(r)$ $NaHCO_3$
$(iv)$ Used as air purifier in submarine	$(s)$ $Na_2CO_3$

Match List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. Chlorophyll	$I$. $Na_2CO_3$
$B$. Soda ash	$II$. $CaSO_4$
$C$. Dentistry,Ornamental work	$III$. $Mg^{2+}$
$D$. Used in white washing	$IV$. $Ca(OH)_2$

Choose the correct answer from the options given below:

Select the correct statement :-
$(a)$ $CaSO_4 \cdot 2H_2O \xrightarrow{393 \ K} CaSO_4 \cdot \frac{1}{2}H_2O + \frac{3}{2}H_2O$
$(b)$ $3Br_2 + 6NaOH \xrightarrow{\text{hot & conc.}} 5NaBr + NaBrO_3 + 3H_2O$
$(c)$ $3Mg + N_2$ $\rightarrow Mg_3N_2$ $\xrightarrow{6H_2O} 3Mg(OH)_2 + 2NH_3 \uparrow$
$(d)$ $2Be + C$ $\rightarrow Be_2C$ $\xrightarrow{4H_2O} 2Be(OH)_2 + CH_4 \uparrow$
Correct answer is :-