Question

$E^{\circ}$ values of some redox couples are given below. On the basis of these values choose the correct option.
$E^{\circ} values : Br_{2}/Br^{-} = + 1.90$; $Ag^{+}/Ag_{\left(s\right)} = + 0.80$;
$Cu^{2+}/Cu\left(s\right) = + 0.34$; $I_{2\left(s\right)}/I^- = + 0.54\, V$

• A. $Cu$ will reduce $Br^-$
• B. $Cu$ will reduce $Ag$
• C. $Cu$ will reduce $I^-$
• D. $Cu$ will reduce $Br^2$

Answer 1

Answer: (D)

More positive the value of $E^{\circ} $, greater is the tendency of the species to get reduced. On the basis of the given $E^{\circ} $ values, $Br_2$ is having highest $E^{\circ} $ value $(+1.90)$ hence, $Cu$ will easily reduce $Br_2$.