What are the oxidation numbers of the underlined elements in each of the following and how do you rationalise your results?
a) `H_(2)underline(S)_(4)O_(6)" "b)underline(F)e_(3)O_(4)`
c) `underline(C)H_(3)underline(C)H_(2)OH" "d)underline(C)H_(3)underline(C)OOH`

Explanation

`H_(2)S_(4)O_(6)` `HO-underset(O)underset(darr)overset(O)overset(uarr)S overset(+5)-S^(@)-S overset(+5)- underset(O)underset(darr)overset(O)overset(uarr)S-OH `
2(1)+4X+6(-2)=0 implies 4X-10=0
.S. average ox, No =2.5 xx = 2.5