Question

The number of $S=O$ bonds present in sulphurous acid, peroxodisulphuric acid and pyrosulphuric acid, respectively are:

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Answer 1

Sulphurous acid $\left(H_{2}S{O}_3\right)$
Peroxodisulphuric acid $\left(H_2{S}_2{O}_8\right)$
Pyrosulphuric acid $\left(H_2{S}_2{O}_7\right)$