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• What type of reaction occurs when a haloalkane is formed from an alcohol?

  Nucleophilic substitution
• What is the word equation for the formation of 2-chloro-2-methylpropane from 2-methylpropan-2-ol?

  2-methylpropan-2-ol + hydrochloric acid → 2-chloro-2-methylpropane + water
• What is the chemical equation for the formation of 2-chloro-2-methylpropane from 2-methylpropan-2-ol?

  CH3C(CH3)2OH + HCl → CH3C(CH3)2Cl + H2O
• What are the 3 main stages in the synthesis of a haloalkane from an alcohol?

  1. Preparation
  2. Separation
  3. Distillation
• Why do two layers form in the separating funnel when synthesizing a haloalkane from an alcohol?

  Different densities and immiscibility of layers
• What is the purpose of anti-bumping granules during distillation?

  To prevent large gas bubbles causing violent boiling
• Why is sodium hydrogen carbonate added to the organic layer after separation?

  To react with any leftover hydrochloric acid
• Why is it important to open the stopper of the separating funnel regularly?

  To release pressure and prevent breakage
• Why is anhydrous sodium sulfate added to the organic mixture after separation?

  To remove small amounts of water
• Why is distillation used when synthesizing a haloalkane from an alcohol?

  To separate and purify the organic product
• What are the key features of the apparatus set-up for distillation?

  • Tilt the condenser down for liquid flow
  • Water enters at the bottom and exits at the top
  • Collection flask should not be airtight
  • Use a thermometer to monitor evaporation
• Why might a water bath or electric heater be used instead of a Bunsen burner?

  If reactants are flammable for safety
• What safety precautions should be taken when carrying out this practical?

  • Keep 2-methylpropan-2-ol away from flames
  • Use a fume cupboard for sulfuric acid
  • Wear safety goggles and gloves
  • Use tongs for hot apparatus
• What is the word equation for the dehydration of cyclohexanol?

  Cyclohexanol → cyclohexene + water
• What is the chemical equation for the dehydration of cyclohexanol?

  $C_6H_{11}OH → C_6H_{10} +$$H_2O$
• What is the role of phosphoric acid in the dehydration of alcohols?

  It acts as a catalyst to speed up the reaction
• Why do two layers form in the separating funnel during alcohol dehydration?

  They have different densities and are immiscible
• Why is it important to open the stopper of the separating funnel regularly?

  To release pressure and prevent breakage
• Why is sodium chloride added to the mixture before separation with a separating funnel?

  To help remove most of the water from the solution
• Why is anhydrous calcium chloride added to the crude product of cyclohexene?

  To remove the final traces of water
• What type of apparatus is used when producing cyclohexene from cyclohexanol?

  Reflux apparatus
• What type of apparatus is used in the purification of crude cyclohexene?

  Distillation apparatus
• What is the purpose of anti-bumping granules during distillation?

  To prevent large gas bubbles causing violent boiling
• What are the key features of the apparatus set-up for distillation?

  • Tilt the condenser down for liquid flow
  • Water enters at the bottom and exits at the top
  • Collection flask should not be airtight
  • Use a thermometer to monitor evaporation
• How can percentage yield be calculated?

  (Actual yield ÷ theoretical yield) x 100
• What is the chemical test for an alkene?

  Add bromine water; color change indicates presence
• Why might a water bath or electric heater be used instead of a Bunsen burner?

  To avoid safety risks with flammable reactants
• What safety precautions should be taken during this practical?

  • Ventilate the lab due to cyclohexanol
  • Wear goggles and gloves for phosphoric acid
  • Use goggles for anhydrous calcium chloride
  • Wash hands after handling cyclohexene
  • Secure stopper on separating funnel when shaking