Final answer:
The balanced equation for the half reaction that occurs in basic solution is given in option c, which shows the correct stoichiometry and charge balance for the reaction between CoCl2 and Na2O2 to form Co(OH)3 and Cl- in a basic solution.
Step-by-step explanation:
The balanced equation for the half reaction that occurs in basic solution can be determined using the half-reaction method. This technique involves balancing the number of atoms and charges in the reaction. For each option provided, we must check if the atoms and charges balance on each side of the equation.
- Option a is not balanced in terms of oxygen atoms.
- Option b has the correct stoichiometry for the reactants and products but does not conserve charge.
- Option c is the balanced half-reaction in a basic solution. It balances the atoms of each element and the electric charge. Here, the cobalt and chlorine atoms are balanced, and the addition of water and hydroxide ions on the appropriate sides results in a balanced equation where both the number of atoms on each side and the charge are equal.
- Option d does not provide the correct stoichiometry for the sodium species.
The correct option is c, which provides a balanced half-reaction in a basic solution: 2CoCl2 + 3Na2O2 + 4H2O → 2Co(OH)3 + 3Cl- + 6OH- + 3Na.