Oxidation number of P in `PO_(4)^(3-)`, of S in `SO_(4)^(2-)` and that of `Cr_(2)O_(7)^(2-)` are respectively

Options

A. `+5+6` and `+6`
B. `+3+6` and `+5`
C. `+5+3` and `+6`
D. `-3+6` and `+6`

Answer

A

Explanation

(i) Oxidation state of `P` in `PO_(4)^(3-)`,
`x+4xx(-2)=-3`
or `x=+5`
(ii) Oxidation stateof `S` in `SO_(4)^(2-)`
`x+4xx(-2)=-2`
or `x=+6`
(iii) Oxidation state of `Cr` in `Cr_(2)O_(7)^(2-),`
`2x+7xx(-2)=-2`
or `2X=12`
or `X=+6`