Dichromate titrations - oxidation reduction titrations

These are titrations where, potassium dichromate is utilized as an oxidising agent in acidic medium. The medium is organized acidic by the make use of dilute sulphuric acid. The potential reaction is

K₂Cr₂O₇ + 4h₂SO₄ → K₂SO₄ + Cr₂ (SO₄)₃ + 4 H₂0 + 3[O]

OR Cr₂ O²-₇ + 14 H⁺ + 6e^- → 2 CR³⁺ + 7 H₂O

The solution of potassium dichromate can be directly employed for titrations. It is generally used for the estimation of ferrous salts and iodides. In the titration of K₂Cr₂O₇ versus ferrous salt either an external indicator that is potassium ferricyanide or an internal indicator that is diphenyl amine can be used.