Question

Consider oxoacids of $N,S$ and $Cl$.
(I) $HN{O}_2,HN{O}_3,H_2{N}_2{O}_2$
(II) $H_{2}S{O}_3,H_{2}S{O}_4,H_2{S}_2{O}_3$
(III) $HCIO,HCI{O}_2,HCI{O}_3,HCI{O}_4$
Strongest acid in each case is

	(I)	(II)	(III)
(a)	$HN{O}_3$	$H_{2}S{O}_4$	$HCl{O}_4$
(b)	$H_2{N}_2{O}_2$	$H_2{S}_2{O}_3$	$HClO$
(c)	$HN{O}_3$	$H_{2}S{O}_3$	$HCl{O}_3$
(d)	$HN{O}_3$	$H_{2}S{O}_3$	$HCl{O}_3$

• A. a
• B. b
• C. c
• D. d

Answer 1

Answer: (A)

Greater the oxidation number of the central atom, stronger is the acid

(I) $\underset{+3}{HN{O}_2}\underset{+5}{HN{O}_3}\underset{+1}{H_2{N}_2{O}_2}$

(II) $\underset{+4}{H_{2}S{O}_3}\underset{+6}{H_{2}S{O}_4}\underset{+2}{H_2{S}_2{O}_3}$

(III) $\underset{+1}{\mathrm{HCl}}\underset{+3}{HCl{O}_2}\underset{+5}{HCl{O}_3}\underset{+7}{HCl{O}_4}$

In $(I):HN{O}_3(II):H_{2}S{O}_4(III):HCl{O}_4$