Sum of π -bonds present in peroxodisulphuric acid and pyrosulphuric acid is

The structure of peroxodisulphuric acid $\left({\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8\right)$ is

Each sulphur is having $2\mathrm{\pi }$ bonds. Hence, total number of $\mathrm{\pi }$-bonds in peroxydisulphuric acid is four.

The structure of pyrosulphuric acid $\left({\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_7\right)$ is

Each sulphur is having $2\mathrm{\pi }$ bonds. Hence, total number of $\mathrm{\pi }$-bonds in pyrosulphuric acid is four.

So, sum of $\mathrm{\pi }$ bonds present = 4 + 4 = 8