<Tr> <Th> Classification </Th> <Td> Colorimetric method </Td> </Tr> <Tr> <Th> Analytes </Th> <Td> Monosaccharides </Td> </Tr> <P> Fehling's solution is a chemical reagent used to differentiate between water - soluble carbohydrate and ketone functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reagent test . The test was developed by German chemist Hermann von Fehling in 1849 . </P> <P> Fehling's solution is prepared by combining two separate solutions, known as Fehling's A and Fehling's B. Fehling's A is aqueous solution of copper (II) sulfate, which is deep blue . Fehling's B is a colorless solution of aqueous Potassium sodium tartrate (also known as Rochelle salt) made in a strong alkali, commonly with sodium hydroxide . Typically, the L - tartrate salt is used . The copper (II) complex in Fehling's solution is an oxidizing agent and the active reagent in the test . </P>

What is fehling's solution used to test for