B05 Oxidation of Alcohols by Potassium Dichromate

Description
Three different butanols in separate test tubes are mixed with an orange potassium dichromate solution.

1. The primary butanol solution turns blue and two phases separate.

2. The secondary butanol solution turns blue.

3. The tertiary butanol solution does not react.

Equation
alcohol + Cr2O72- + 14 H+ --> (ketone or aldehyde) +2 Cr3+ + 7 H2O

Reference
L. R. Summerlin, C. L. Borgford, and J. B. Ealy,"Chemical Demonstrations A Sourcebook for Teachers",Vol. 2, American Chemical Society, Washington, DC, (1987) p.210.