Ketose

A ketose is a sugar containing one ketone group per molecule.

With 3 carbon atoms, dihydroxyacetone is the simplest of all ketoses and is the only one having no optical activity.

List of ketoses

 * Trioses: dihydroxyacetone
 * Tetroses: erythrulose
 * Pentoses: ribulose, xylulose
 * Hexoses: fructose, psicose, sorbose, tagatose

Qualitative reaction
General qualitative reaction for ketoses is Seliwanoff's test.