Question

Oxidation number of ${}^{\prime }{S}^{\prime }$ in Marshalls acid is:

• A. 6
• B. 5
• C. 7
• D. 3

Answer 1

The correct option is A 6

Oxidation number of ${}^{\prime }{S}^{\prime }$ in Marshall's acid $\left(H_2{S}_2{O}_8\right)$ is +6.
The structure is:

Here, two 'O' Atoms are present in peroxide linkage i.e. O. N. of oxygen = -1
Thus, $2(+1)+2x+2(-1)+6(-2)=0$
Or x = +6