Tests and observations for organic compounds

• Test and observations for -

  Alkene


  Test: 

  Add bromine water

  Observation: 

  Bromine water is decolourised (orange to colourless)
• Test and observations for -

  Haloalkane


  Test:

  Add silver nitrate and ethanol and place in water bath @ 50°C

  Observation:

  Cl - White precipitate

  Br - Cream precipitate

  I - Yellow precipitate
• Test and observations for -

  Carbonyl

  Test:

  Add 2,4-dinitrophenylhydrazine (2,4-DNP/Brady's reagent)

  Observation:

  Orange precipitate
• Test and observations for -

  Aldehyde


  Test:

  Add ammoniacal silver nitrate (Tollen's reagent) and warm

  
  

  Observation:

  Silver mirror
• Test and observations for -

  Primary and secondary alcohols and Aldehydes


  Test:

  Add acidified potassium dichromate(VI) and warm in water bath

  Observation:

  Colour change orange to green
• Test and observations for -

  Carboxylic acid


  Test:

  Add aqueous sodium carbonate

  Observation:

  Effervescence
• Test and observations for -

  Phenol


  Test:

  Add Br2

  Test pH using a pH meter/indicator

  
  

  Observation:

  Bromine is decolourised and white precipitate forms

  pH < 7 and No effervescence