Complete and balance the equation.

Br2 (g) + KI (g) =

Which element or ion is oxidized and which is reduced?

Which one is the oxidizing agent and which is the reducing agent?

For completing the equation, you should know that the more reactive halogen will displace the less reactive one, and this reactivity increases up the halogen group in the periodic table.

I have a little 'trick' to determine oxidising agents and reducing agents. You need to remember :" OIL RIG "

Oxidation
Is
Loss of Electrons

Reduction
Is
Gain of Electrons

Which element or ion loses an or more electrons? If it loses electrons, it is oxidised. If it gains, it is reduced.

Now, what is an oxidising agent? It is a substance that causes oxidation, while it is itself reduced. The substance having been reduced is the oxidising agent (or oxidant) and the one which got oxidised is the reducing agent (or reductant)

Hope it helped!! :)