For the redox reaction:
`Cr_(2)O_(7)^(2-)+H^(o+)+NirarrCr^(3+)+Ni^(2)+H_(2)O`
The correct coefficient of the reactants for the balanced reaction are:

Options

A. `Cr_(2)O_(7)^(2-)=1, Ni=3, H^(o+)=14`
B. `Cr_(2)O_(7)^(2-)=3, Ni=3, H^(o+)=12`
C. `Cr_(2)O_(7)^(2-)=2, Ni=3, H^(o+)=14`
D. `Cr_(2)O_(7)^(2-)=1, Ni=1, H^(o+)=16`

Answer

A

Explanation

`14H^(o+)+cancel(6e^(-))+Cr_(2)O_(7)^(2-)rarr2Cr^(3+)+7H_(2)O`
`2x=14=-2, 2x=6`
`2x=12`
`NirarrNi^(+2)+cancel(2e^(-))]xx3`
`ulbar(14H^(o+)+CrO_(7)^(2-)+3Ni2Cr^(3+)+3Ni^(2+)+7H_(2)O)`