CBSE 2026 · Region 4 · Set 1 · Q9 · 1 mark
Consider the following cell at $\displaystyle 298$ K : $\displaystyle \mathrm{Mg}(\mathrm{s})\left|\mathrm{Mg}^{2+}(1 \cdot 0 \mathrm{M})\right|\left|\mathrm{Cu}^{2+}(1 \cdot 0 \mathrm{M})\right| \mathrm{Cu}(\mathrm{s})$ How can we increase the emf of the cell using the same substances ?
Official answer
From CBSE’s own marking scheme for this paper.
(A)
By decreasing only the $\displaystyle \left[\mathrm{Mg}^{2+}\right]$ to $\displaystyle 0 \cdot 1 \mathrm{M}$
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CBSE Class 12 Chemistry past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.