Chemistry · 2021
JEE Main · 4 August 2021, Shift 1 · Q56
For the reaction, 6 I^-_( aq ) + Cr_2 O_7^2-_( aq ) +14 H^+ → 3 I_2( aq ) +2 Cr^3+_( aq ) +7 H_2 O_( aq ); E_cell^0=0.79 V The standard reduction…
For the reaction,
$$6 \mathrm{I}^{-}{ }_{(\mathrm{aq})}+\mathrm{Cr}_2 \mathrm{O}_7^{2-}{ }_{(\mathrm{aq})}+14 \mathrm{H}^{+} \longrightarrow 3 \mathrm{I}_{2(\mathrm{aq})}+2 \mathrm{Cr}^{3+}{ }_{(\mathrm{aq})}+7 \mathrm{H}_2 \mathrm{O}_{(\mathrm{aq})} ; \mathrm{E}_{\mathrm{cell}}^0=0.79 \mathrm{~V}
$$
The standard reduction potential for $\displaystyle \mathbf{I}_{2(\mathrm{aq})}$ is $\displaystyle x \times 10^{-2} \mathrm{~V}$. The value of $\displaystyle x$ is \_\_\_\_. (Nearest integer)
[Given : The standard reduction potential for $\displaystyle \left(\mathrm{Cr}_2 \mathrm{O}_7{ }^{2-}{ }_{(\mathrm{aq})} \rightarrow 2 \mathrm{Cr}^{3+}\right.$ is $\displaystyle 1.33$ V]
Official answer
54
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JEE Main 2021 Chemistry question, with the answer from NTA’s final answer key. Where our answers come from.