If I did this correctly the balanced equation would be: 14H⁺+Cr₂O₇²⁻+6I⁻→3I₂+2Cr³⁺+7H₂O
oxidation half: (iodide was oxidized) 2I⁻→I₂+2e⁻
reduction half: (chromium was reduced) 14H⁺+Cr₂O₇²⁻+6e⁻→2Cr³⁺+7H₂O
H⁺ comes from the solution. It is in the final reaction since in redox reactions the oxygen is turned into water since it can't just go away. I multiplied the oxidation half reaction by 3 in order for both half reactions to half the same number of electrons since equal numbers of electrons need to be lost and gained for the reaction to be balanced.
I hope this helps. Let me know if anything is unclear.
