PAG 5.2 Questions and Answers | Latest Update | Graded A+

PAG 5.2 Questions and Answers | Latest Update | Graded A+ **How do you synthesize cyclohexane from cyclohexanol (excluding purification)?** 1. Place cyclohexanol in a small round-bottom or pear-shaped flask. 2. Add concentrated phosphoric acid slowly, mixing thoroughly. 3. Add anti-bumping granules to the mixture. 4. Set up the apparatus for reflux using a water bath, electric heater, or sand bath. 5. Heat the mixture under reflux at approximately 70°C for 15 minutes. 6. Stop heating and allow the apparatus to cool for a few minutes. 7. Rearrange the apparatus for distillation. 8. Gradually raise the temperature and collect the distillate between 70°C and 90°C. **What equipment is needed for this process?** - Goggles - Anti-bumping granules - Measuring cylinder (10 cm3) - Small funnel - Quickfit apparatus: - Pear-shaped flask - Still head - Thermometer - Liebig condenser and tubing - Receiver **How do you purify the cyclohexane?** 1. In a separating funnel, add an equal volume of saturated sodium chloride solution to the distillate and gently shake to release any pressure. 2. Allow the layers to separate and discard the lower aqueous layer. 3. Transfer the organic layer to a small conical flask. 4. Add anhydrous calcium chloride to the organic layer and swirl. 5. Pour the clear liquid into a weighed container and reweigh to determine the mass of cyclohexane. **What is the purpose of the sodium chloride?** It assists in separating the mixture into two distinct layers. What equipment is needed Balance accurate to 2.d.p Wash bottle with deionised water Separating funnel with stopper (50cm) Anhydrous CaCl How do you test for cyclohexane Test for the carbon-carbon double bond Add bromine and it should turn from orange to colourless