Which of the following chemicals may be used to identify three unlabelled beakers containing conc. $NaOH$,conc. $H_{2}SO_{4}$ and water?

Prolonged heating is avoided during the preparation of ferrous ammonium sulphate to:

Match Column-$I$ and Column-$II$ with the correct relation:

Column-$I$	Column-$II$
$(i)$ Ammonium phosphomolybdate	$(a)$ $(NH_4)_2MoO_4$
$(ii)$ Ammonium phosphate	$(b)$ $Mg^{2+} + NH_4OH$
$(iii)$ Mixture of magnesia	$(c)$ $H_3PO_4$
$(iv)$ Ammonium molybdate	$(d)$ $(NH_4)_3PO_4$
$(v)$ Phosphoric acid	$(e)$ $(NH_4)_3PO_4 \cdot 12MoO_3$

$CaCO_3$ (aqueous suspension) $\xrightarrow{AcOH}$ $\xrightarrow{Na_2C_2O_4 \text{ solution}}$
Which of the following observations is correct for the above experiment?

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

List-$I$ (Complex)	List-$II$ (Colour)
$A$. $Mg(NH_4)PO_4$	$I$. Brown
$B$. $K_3[Co(NO_2)_6]$	$II$. White
$C$. $MnO(OH)_2$	$III$. Yellow
$D$. $Fe_4[Fe(CN)_6]_3$	$IV$. Blue

Choose the correct answer from the options given below:

The number of white coloured salts among the following is .................
$A$. $SrSO_4$ $B$. $Mg(NH_4)PO_4$ $C$. $BaCrO_4$ $D$. $Mn(OH)_2$ $E$. $PbSO_4$ $F$. $PbCrO_4$ $G$. $AgBr$ $H$. $PbI_2$ $I$. $CaC_2O_4$ $J$. $[Fe(OH)_2(CH_3COO)]$