SC23

• Alcohols have a functional group of -OH and can all do displacement reactions where a water molecule is lost to form an acid.

  ethanol ---> ethanoic acid + water
• Alcohol as Fuel Practical:

  1. Measure out a known volume of water and add it to a beaker
  2. Record the mass of a spirit burner and place it underneath the beaker
  3. Record the starting water temperature using a thermometer
  4. Light the fuel and heat the water up for a set time period or temperature increase
  5. Extinguish the flame once requirement is met and record the final temperature as well as the changed mass of the spirit burner

  Experiment values won't be precise as a large amount of heat was dissipated to the surroundings.

  This can be reduced by insulating the beaker or adding a lid
• Alcohol as Fuel Practical Safety:

  • allow objects to cool before handling
  • keep alcohol away from uncontrollable fire
  • wear safety goggles
  • keep loose items away (hair, paper, clothes ext.)
• The functional group of carboxylic acids is -COOH and all can have reactions typical of acids like neutralisation.

  They are weak acids and tend to turn universal indicator orange
• Alcohols can be oxidised to form carboxylic acids and water
• All members of the same homologous series have similar reactions due to their shared functional group
• Ethanol can be produced in two ways:

  1. React ethene with steam at raised temperatures and over a catalyst
  2. Fermentation of sugar in aqueous solution (requires the catalyst yeast)
• Alcohol Purification:

  • once sugar solution has been fermented, the alcohol produced needs to be separated from the mixture
  • fractional distillation is used to separate ethanol and water
• Fermentation - a process that adds yeast to sugars under anaerobic conditions to produce alcohol and carbon dioxide

  If oxygen is present then yeast will respire aerobically to produce water, carbon dioxide and a carboxylic acid