Assign oxidation numbers to all atoms in the following equation, write each half reaction, and the identify which element is oxidized and which is reduced.

CL2 + 2HBr --> 2HCL + Br2

Oxidation numbers:

Cl2: 0
HBr: +1
HCl: -1
Br2: 0

Half Reactions:
Oxidation: Cl2 --> 2Cl-
Reduction: 2H+ + 2Br- --> HBr

Element oxidized: Chlorine
Element reduced: Hydrogen