Which from following statements is true regarding the cell emf at 298 K for
${ }^{\ominus} \mathrm{Ni}_{(s)}|\stackrel{+2}{\mathrm{~N}} \mathrm{i}(0.01 \mathrm{M}) \| \stackrel{+}{\mathrm{Ag}}(0.01 \mathrm{M})| \stackrel{\oplus}{\mathrm{Ag}_{(s)}}$
The standard emf for cell, ${ }^{\ominus} \mathrm{Cd}_{(\mathrm{s})}\left|{ }^{+2} \mathrm{Cd}(1 \mathrm{M}) \| \stackrel{+2}{\mathrm{Cu}}(1 \mathrm{M})\right| \mathrm{Cu}_{(\mathrm{s})}{ }^{\oplus}$ is 0.74 V .
If concentration of $\mathrm{Cd}_{(\mathrm{aq})}^{+2}$ and $\mathrm{Cu}_{(\mathrm{aq})}^{+2}$ decreases by 10 times at 298 K . Calculate emf of cell.
A hypothetical galvanic cell is ${ }^{\ominus} \mathrm{A}_{(\mathrm{s})} \mid \stackrel{+}{\mathrm{A}}(1 \mathrm{M})\|\stackrel{+2}{\mathrm{~B}}(1 \mathrm{M})\| \stackrel{\oplus}{\mathrm{B}}_{(\mathrm{s})}$ and emf of cell is positive. What is the possible cell reaction?
Consider galvanic cell, ${ }^{\ominus} \mathrm{A}_{(\mathrm{s})}\left|\mathrm{A}_{(\mathrm{aq})}^{+2}\right|\left|\mathrm{B}_{(\mathrm{aq})}^{+}\right| \mathrm{B}_{(\mathrm{s})}^{\oplus}$
if emf of cell is positive, identify a correct cell reaction from following.