Question

Peroxy acids of sulphur are:

• A. $H_2{S}_2{O}_8$
• B. $H_{2}S{O}_5$
• C. $H_2{S}_2{O}_7$
• D. $H_2{S}_2{O}_3$

Answer 1

Answer: (A), (B)

$H_{2}S{O}_5$

For the acid to be a 'peroxy' acid, it should have a 'peroxy' linkage - much like the $-O-O-$ bond:

Both the above are peroxy acids.

$H_2{S}_2{O}_3$ is thiosulphuric acid; it is similar to sulphuric acid but one with an $S-S$ double bond.