Chromium(III) hydroxide can be oxidized in basic solution by hypochlorite ion…
CHEMISTRY · Multi-part · A Level · Chemistry · Oxidation, reduction and redox reactions · Oxidation, reduction and redox reactions
Problem
Chromium(III) hydroxide can be oxidized in basic solution by hypochlorite ion according to the following unbalanced skeletal equation:
ClO−+Cr(OH)3+OH−→Cl−+CrO42−+H2O
This reaction is relevant to industrial wastewater treatment in alkaline media.
(a) Assign oxidation numbers to chlorine and chromium in every species in the skeletal equation.
(b) Identify the oxidizing agent and the reducing agent in this process, supporting your claim with the oxidation-number changes from part (a).
(c) Balance the complete ionic equation for the reaction as it occurs in basic solution, ensuring that both mass and charge are conserved and that all coefficients are the smallest possible integers.
(d) Demonstrate explicitly that the total charge on the reactant side equals the total charge on the product side for your balanced equation from part (c).