Tests for:

• Carbonates:

  Add acid - observe fizzing.
• Sulfates:

  Add Ca2+ or lower - observe white precipitate.
• Hydroxide:

  Add Ca2+ or higher - observe white precipitate
• Ester - Sweet smelling.
• Alkene:

  • Bromine water - Colour change from brown to colourless.
  • Acidified Potassium Manganate - Colour change from purple to colourless.
• Halogenoalkanes:

  1. Reflux with aqueous sodium hydroxide
  2. Neutralise with dilute nitric acid
  3. Add silver nitrate

  Results:

  Cl- = White precipitate (AgCl), dissolves in conc and dilute NH3

  Br- = Cream precipitate (AgBr), dissolves in conc NH3

  I- = Pale yellow precipitate (AgI), does not dissolve in NH3
• Alcohols:

  • Reflux with acidified potassium dichromate - colour change from orange to green.
  • Primary - oxidises to Aldehyde - oxidises to carboxylic acid.
  • Secondary - oxidises to ketone
  • Tertiary - does not oxidise
• Carboxylic acid:

  • Add Na2CO3 or NaHCO3 - Observe fizzing or effervescence.
• Phenol:

  • Add bromine water - Colour change from orange-brown to colourless to white precipitate
  • Iron III Chloride - Colour change from pale yellow to purple.
• Aldehydes and Ketones:

  • Add 2,4 DNPH - Orange-red precipitate
• Aldehydes:

  • Reflux with acidified potassium dichromate - colour change from orange to green.
  • Reflux with acidified potassium manganate - colour change from purple to colourless
  • Tollens reagent: - Add a small amount to the test tube (in water bath) - silver mirror (distinguish between aldehyde and ketone as ketone does not react)
  • Fehling's Reagent: - Warm together in test tube, colour change from blue to red-brown precipitate
• Amine:

  • HNO2 (made in situ NaNO2 + HCL) - Observe bubbles.
• Amide:

  • Hydrolyse - Smells fishy.