Question

Question #82f6e

Answer 1

`K` is being oxidized,
`Cu` is being reduced

Explanation:

Since oxidation is the gain in oxidation state (loss of electrons), `K` is being oxidized because it has on oxidation state of `0` originally, and as the reaction proceeds, its oxidation state is raised to `+1`.

Since reduction is the lowering in oxidation state (gain of electrons), `Cu` is being reduced because it has on oxidation state of `+2` originally, and as the reaction proceeds, its oxidation state is lowered to `0` from becoming pure `Cu`.