Video: Dichromate ion as an oxidizing agent I
Dichromate ion is a strong oxidizing agent:Cr2O72-(aq) + 14 H+(aq) + 6 e- ® 2 Cr3+(aq) + 7 H2O(l)
In this case, dichromate ion oxidizes iodide ion to iodine. The molecular iodine is extracted into dichloromethane to give the characteristic purple color.
2 I-(aq) ® I2(aq) + 2 e-