Illustrated Glossary of Organic Chemistry

Benedict's test: A chemical reaction used to test for the presence of an aldehyde in an unknown, frequently a carbohydrate. To perform the test, one adds Benedict's solution (a blue solution containing Cu²⁺) to the material to be tested. If an aldehyde is present, a brick red Cu₂O precipitate is formed.

	Add glucose
Benedict's solution is blue (due to Cu2+) before addition of the unknown.		A positive Benedict's test is indicated by a yellowish to red precipitate of Cu2O.