Illustrated Glossary of Organic Chemistry

Precipitate: In chemistry, a solid formed by a change in a solution, often due to a chemical reaction or change in temperature that decreases solubility of a solid. In meteorology a precipitate is liquid or solid water (rain, snow, etc.) falling from the sky.


 Fehling's solution is blue due to dissolved Cu2+. The solution is homogeneous. There is no precipitate.

Add glucose

Addition of glucose causes reduction of Cu2+ to red Cu2O, forming a precipitate at the bottom of the test tube.