Charge (q)=it=2×8×60=960C
96000960=0.01F
Cr2O72−+14H++6e−→2Cr3++7H2O
0.01F31×0.01mole
Theoritical mass of Cr3+=31×96000600×52=0.173g
So, efficiency =WTheoritialWactual×100=0.1730.104×100=60
JEE Main 2020 — Chemistry Physical Chemistry
An acidic solution of dichromate is electrolyzed for 8 minutes using 2 A current. As per the following equation
Cr2O72+14H++6e−→2Cr3++7H2O
The amount of Cr3+. obtained was 0.104g. The efficiency of the process (in is (Take : F=960000C, At. mass of chromium =52)
Held on 3 Sept 2020 · Verified 6 Jul 2026.
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