Question: what is fehling solution formula?
Answer: The deep blue active ingredient in Fehling's solution is the bis(tartrate) complex of Cu 2+. The net reaction between an aldehyde and the copper(II) ions in Fehling's solution may be written as: RCHO + 2 Cu 2+ + 5 OH − → RCOO − + Cu 2O + 3 H 2O.