How many electrons are transferred during following change $2{\mathrm{I}}^{-}\left(\mathrm{aq}\right)\to {\mathrm{I}}_2\left(\mathrm{s}\right)$?

Redox Reaction

1. Redox reactions are oxidation- reduction reactions in which the reactants change their oxidation states.
2. Any half reaction can be broken down into half reactions one is oxidation and other is reduction.
3. $2{\mathrm{I}}^{-}\left(\mathrm{aq}\right)\to {\mathrm{I}}_2\left(\mathrm{s}\right)$ In this reaction, two electrons are transferred and the oxidation number of Iodine(I) changes from $-1$ to $0$.

Therefore, two electrons are transferred during this change.