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

List-$I$	List-$II$
$A$. $Na_2CO_3 \cdot 10H_2O$	$I$. $Caustic \ soda$
$B$. $NaOH$	$II$. $Slaked \ lime$
$C$. $Ca(OH)_2$	$III$. $Baking \ soda$
$D$. $NaHCO_3$	$IV$. $Washing \ soda$

$A$ 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

The correct solubility order is/are:
$I. CaCO_3 > SrCO_3 > BaCO_3$
$II. Li_2CO_3 < Na_2CO_3 < K_2CO_3$
$III. K_2CO_3 < Rb_2CO_3 < Cs_2CO_3$
$IV. Na_2CO_3 > K_2CO_3 > Rb_2CO_3$

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 :-

What is the mixture of $MgCl_2$ and $MgO$ called?

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