The oxidation state of chromium, in the final product formed by the reaction between KI and acidified potassium dichromate solution is:
Answer & explanation
Correct answer: option 2
The correct answer is option 2. +3.
The reaction between KI and acidified potassium dichromate solution is a redox reaction. In a redox reaction, electrons are transferred from one reactant to another. In this reaction, the iodide ions \((I^-)\) are oxidized to iodine \((I_2)\), and the chromium ions \((Cr^{3+})\) in potassium dichromate \((K_2Cr_2O_7)\) are reduced to chromium(III) oxide \((Cr_2O_3)\).
The oxidation state of chromium in \((K_2Cr_2O_7)\) is +6, and the oxidation state of chromium in \((Cr_2O_3)\) is +3. Therefore, the oxidation state of chromium in the final product is +3.
The balanced equation for the reaction is as follows:
\(6KI + K_2Cr_2O_7 + 7H_2SO_4 → 3I_2 + 4K_2SO_4 + Cr_2O_3 + 7H_2O\)