FEHLING'S TEST

• WHAT IS FEHLING'S SOLUTION MADE UP OF?

  Fehling A

  -> Cu (2+) ion that colours the solution blue

  Fehling B

  -> contains alkali and complexing agent
• FEHLING'S TEST OF ALDEHYDES?

  • aldehyde warmed with Fehling's solution
  • brick red precipitate of Cu (I) oxide produced
• WHY IS A Cu (I) OXIDE PRODUCED WHEN REACTING WITH ALDEHYDE?

  Cu (II) oxidises aldehyde to carboxylic acid and is reduced to Cu (I)
• WHAT HAPPENS WHEN KETONES ARE REACTED WITH FEHLING'S SOLUTION?

  no reaction