Oxidation of Alcohols

• Using Potassium Dichromate and the heating on we can classify alcohols into primary, secondary and tertiary alcohols:

  
  

  Primary Alcohols can be oxidised and through distillation to form a Aldehyde

  Colour changes from orange to green

  Then: Aldehyde can be further oxidised into forming a carboxylic acid in reflux conditions

  
• Using potassium dichromate and the heating on we can classify alcohols into primary, secondary and tertiary alcohols:

  Secondary alcohols form a ketone in reflux conditions

  Colour changes from orange to green

  Tertiary alcohols have no visible change as there are no hydrogens bonded to the carbon

  
• Tollens test:

  The Tollens reagent is made by combining AgNO3 with excess aqueous ammonia(NH3) and heating

  If a Aldehyde - Ag gets reduced and forms a silver mirror

  Ketones form no visible change as they cannot be oxidised
• Fehling's solution

  Fehling's solution is made up by adding a solution of Cu2+ ions to potassium tartrate dissolved in sodium hydroxide(NaOH) this forms a blue solution

  If a Aldehyde is present Cu gets reduced and the blue solution turns into a red/brown precipitate

  If a Ketone - No visible change