The Jones oxidation is an organic reaction used to oxidize alcohols using chromic trioxide and acid in water. A primary alcohol is oxidized to an aldehyde or all the way to a carboxylic acid, while a secondary alcohol to a ketone. The mechanism begins with the reaction of CrO3 with acid (often H2SO4) to form chromic acid or dichromic acid in more concentrated solutions. The alcohol oxidation then occurs with chromic acid which in turn gets reduced in the process.
Bowden, K.; Heilbron, I. M.; Jones, E. R. H.; Weedon, B. C. L. J. Chem. Soc. 1946 39–45.