`Cr_(2)O_(7)^(-2)+14H^(+)+6Fe^(+2)rarr2Cr^(+3)+6Fe^(+3)+7H_(2)O`
Given : `E^(@)(Cr_(2)O_(7)^(-2),H^(+),2Cr^(+3)//Pt)=1.33V` ,
`(Fe^(+3),Fe^(+2)//Pt)=+0.77V` at 298 K
Upon discharge of the cell for 80 min at one ampere, the anode was found to have decreased in mass by

Options

A. `5.4 g`
B. `10.8 g`
C. `8.2 g`
D. zero

Answer

D

Explanation

Since the reaction at anode is `Fe^(2+)rarr Fe^(3+)+e^(-)` and `Fe^(2+)` and `Fe^(3+)` appearin the solution, there will be no change in the mass of anode which is inert electrode.