CBSE 2026 · Region 2 · Set 1 · Q1 · 1 mark

Consider the following reaction : \[\mathrm{Zn}_{(\mathrm{s})}+\mathrm{Ag}_{2} \mathrm{O}_{(\mathrm{s})}+\mathrm{H}_{2} \mathrm{O}(\mathrm{l}) \rightarrow \mathrm{Zn}_{(\mathrm{aq})}^{2+}+2 \mathrm{Ag}_{(\mathrm{s})}+2 \mathrm{OH}_{(\mathrm{aq})}^{-} \] Given : $\displaystyle \mathrm{E}^{0}{ }_{\mathrm{Ag}^{+} / \mathrm{Ag}}=0.80 \mathrm{~V}$ \[\begin{aligned} & \mathrm{E}_{\mathrm{Zn}^{2+} / \mathrm{Zn}}=-0.76 \mathrm{~V} \\ & 1 \mathrm{~F}=96500 \mathrm{C} \mathrm{~mol}^{-1} \end{aligned} \] $\displaystyle \Delta_{\mathrm{r}} \mathrm{G}^{\circ}$ for the above reaction is :

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.