MCQ
The conjugate acid of ${H_2}PO_4^ - $ is
- ✓${H_3}P{O_4}$
- B${H_2}PO_4^ - $
- C$PO_4^{3 - }$
- D${H_3}{O^ + }$
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($1$) $W$ and $\mathbf{X}$ are, respectively
$[A]$ $O_3$ and $P_4 O_6$ $[B]$ $O_2$ and $P_4 O_6$ $[C]$ $O_2$ and $P_4 O_{10}$ $[D]$ $O_3$ and $P_4 O_{10}$
($2$) $Y$ and $Z$ are, respectively
$[A]$ $N_2 O_3$ and $\mathrm{H}_3 \mathrm{PO}_4$
$[B]$ $N_2 O_5$ and $\mathrm{HPO}_3$
$[C]$ $N_2 O_4$ and $HPO_3$
$[D]$ $N_2 O_4$ and $H_3 PO_3$
Give the answer of quetion ($1$) and ($2$)