Wine is a mixture that is mainly ethanol and water. A student separates ethanol from wine using fractional distillation.
The wine is heated in a flask. A fractionating column packed with glass beads is fitted on top of the flask. A thermometer is placed at the top of the column, next to the side arm that leads to a condenser. The liquid from the condenser is collected in a beaker.
The boiling point of ethanol is 78 °C and the boiling point of water is 100 °C.
Explain why ethanol is the first liquid collected in the beaker.
State the temperature shown on the thermometer while ethanol is being collected.
Give the purpose of the condenser.
Explain why simple distillation would not separate the ethanol from the water well.
Suggest why the student heats the flask with an electric heater instead of a Bunsen burner.
48 exam-style questions on Edexcel GCSE Chemistry 3.2 Methods of separating and purifying substances, covering 3.2.1 Pure substances and mixtures, 3.2.2 Techniques for separating mixtures, 3.2.3 Paper chromatography and Rf values, and 3.2.4 Making water potable. Each one has a worked solution and a mark scheme showing where the marks go.