Question

Oxidation number of $P$ in $P{O}_4^{3-}$, of $S$ in $S{O}_4^{2-}$ and that of $Cr$ in $C{r}_2{O}_7^{2-}$ are respectively:

• A. +3, +6 and +6
• B. +5, +6 and +6
• C. +3, +6 and +5
• D. +5, +3 and +6

Answer 1

The correct option is B +5, +6 and +6

$P{O}_4^{3-}$, Oxidation No. of $P=+5$

$S{O}_4^{2-}$, Oxidation No. of $S=+6$

$C{r}_2{O}_7^{2-}$ , Oxidation No. of $Cr=+6$