Answer
I is oxidized
Cl is reduced
Work Step by Step
Cl2 + 2NaI --> I2 + 2NaCl
Cl2 and I2 are in their elemental state so they have an oxidation state of 0.
For NaI, Na has an oxidation state of +1 since it is an alkali metal so that means I must be I- and have an oxidation state of -1.
Therefore, I goes from -1 on the left to 0 on the right.
I loses electrons (is oxidized)
For NaCl, Na is once again +1 since it is an alkali metal so Cl must be Cl- and -1
Therefore, Cl goes from 0 on the left to -1 on the right
Cl gains electrons (is reduced)
