What harris doesn't know

• what happens during oxidation of an alcohol and what conditions are required?

  • potassium dichromate K2Cr2O7 acidified with dilute sulfuric acid H2SO4
  • causes orange solution to reduce to a green solution containing chromium ions

  
• what are the products of oxidising a primary alcohol? What is the prep to form a aldehyde?


  • oxidised into aldehyde or carboxylic acid
  • aldehyde can be oxidised into carboxylic acid
  • To ensure an aldehyde is produced the aldehyde has to be distilled as soon as it forms to prevent further reaction with the oxidising agent

  
• what is the preparation of oxidation to form a carboxylic acid?


  • primary alcohol heated strongly under reflux with excess of potassium dichromate= carboxylic acid
  • excess ensures all the alcohol is oxidised
  • heating under reflux ensures that all the aldehyde initially formed oxidises into carboxylic acid

  
• What are the products of oxidising a secondary alcohol?

  • oxidise using potassium dichromate ions and dilute sulfuric acid under reflux to produce a ketone and water
  • orange to green to show complete oxidation

  
• what happens when tertiary alcohols are oxidised?

  Don't undergo oxidation reactions and the dichromate ions remain orange
• what is the dehydration of alcohol?

  when a water molecule is removed= elimination reaction

  alcohol= heated under reflux

  • in the presence of= acid catalyst and concentrated sulfuric acid or phosphoric acid

  produces and alkene and water

  
• how are haloalkanes formed from alcohols?

  Alcohol reacts with hydrogen halide under reflux with:

  - sulfuric acid and sodium halide