Chemistry · 2020
JEE Main · 3 September 2020, Shift 2 · Q48
An acidic solution of dichromate is electrolyzed for 8 minutes using 2A current. As per the following equation Cr_2 O_7^2-+14 H^++6 e^- → 2 Cr^3++7…
An acidic solution of dichromate is electrolyzed for $\displaystyle 8$ minutes using 2A current. As per the following equation
$$\mathrm{Cr}_2 \mathrm{O}_7^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+7 \mathrm{H}_2 \mathrm{O}
$$
The amount of $\displaystyle \mathrm{Cr}^{3+}$ obtained was $\displaystyle 0.104$ g. The efficiency of the process(in%)is (Take : $\displaystyle \mathrm{F}=96000 \mathrm{C}$, At. mass of chromium $\displaystyle =52$ ) \_\_\_\_.
Official answer
60
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