Half-reactions practice problems

1) Cl₂ + 2e¯ ---> 2Cl¯

2) Sn ---> Sn²⁺ + 2e¯

3) Fe²⁺ ---> Fe³⁺ + e¯

4) I₃¯ + 2e¯ ---> 3I¯

5) ICl₂¯ + 2e¯ ---> I¯ + 2Cl¯

6) Sn ---> SnO₂ and NO₃¯ ---> NO₂

7) HClO ---> Cl₂ and Co ---> Co²⁺

8) NO₂ ---> NO₃¯ and NO₂ ---> NO

Note that in this last redox redox equation the NO₂ (actually just the N) is both being reduced AND being oxidized. In the first half-reaction, the N goes from +4 to +5 (oxidation) and in the second, the N goes from +4 to +2 (reduction).

By the way, we could flip the reaction so that NO₃¯ and NO are reacting together to produce only one product, the NO₂. In that case, the two half-reactions would be reversed.