Potassium iodide, KI, is used as a reagent in both inorganic and organic chemistry. A student electrolyses a solution of $$\(\mathrm{KI}(\mathrm{aq})\)$$ for 8 minutes using a direct current. The half-equation for the reaction that occurs at the anode is given. $$\[ 2 \mathrm{I}^{-}(\mathrm{aq}) \rightarrow \mathrm{I}_{2}(\mathrm{aq})+2 \mathrm{e}^{-} \]$$ (i) Write a half-equation for the reaction that occurs at the cathode. Include state symbols. ................................................................................................................................. (ii) After the electrolysis, the $$\(\mathrm{I}_{2}(\mathrm{aq})\)$$ produced requires $$\(21.35 \mathrm{~cm}^{3}\)$$ of $$\(0.100 \mathrm{moldm}^{-3}\)$$ $$\(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}(\mathrm{aq})\)$$ to react completely. $$\[ \mathrm{I}_{2}(\mathrm{aq})+2 \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}(\mathrm{aq}) \rightarrow 2 \mathrm{NaI}(\mathrm{aq})+\mathrm{Na}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}(\mathrm{aq}) \]$$ Calculate the average current used in 8 minutes during the electrolysis. current $$\(=\)$$ .................................................... A

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