MHTCET 23 Apr 2025 Shift 1 Paper

Concept:Standard electrode potential is an intensive property, so its value does not depend on the number of electrons or moles involved.When a reaction is reversed, the sign of its standard potential reverses.Explanation:The given reduction reaction is $\mathrm{Cu}^{2+}_{(aq)} + 2e^- \longrightarrow \mathrm{Cu}_{(s)}$ with $E^\circ = +0.34$ V.The required reaction is $2\mathrm{Cu}_{(s)} \longrightarrow 2\mathrm{Cu}^{2+}_{(aq)} + 4e^-$.This reaction is exactly the reverse of the given reduction reaction, multiplied by 2.Reversing the reaction changes the sign of $E^\circ$.So, the potential becomes $-0.34$ V.Since $E^\circ$ is an intensive property, multiplying the reaction by 2 does not change its value.Hence, the standard potential for the given oxidation reaction remains $-0.34$ V.Answer:The standard potential is $-0.34$ V, which matches option D.