Question

Co(s) is placed into a solution containing Au+(aq). A redox reaction occurs, the products of which are Co3+(aq) and Au(s), what is the balanced redox equation?

Answer 1

The reaction described above is a single-replacement reaction as Co was able to replace Au in the solution. The redox reaction involves a process in which one agent is reduced while the other one is oxidized. The ionic equation can be expressed as,

           Co(s) + Au⁺(aq) --> Co³⁺(aq) + Au(s)

If we are to balance the equation such that equal number of electrons will be in both sides of the equation, this will become.

       Co(s) + 3Au⁺(aq) --> Co³⁺ + 3Au(s)