Solutions: Chromatography

1. Solutions: Chromatography Year 7 WC 18th November Lesson 2

2. Chromatography • WALT: Describe the process of chromatography and why it is useful • I must be able to suggest one alternative solvent to water • I should be able to successfully carry out a practical on chromatography • I could suggest several ways in which chromatography might be useful in ‘real life’

3. So far we’ve learnt… • That fractional distillation is useful for ………. • That to recover a solvent from a liquid solution, we can use ………………… • That to recover solutes from a liquid solution, we could :

4. Today, we will use chromatography • Chromatography is useful for separating mixtures of different soluble substances. It works when the substances have different solubilities.

5. Turn to page 170 You will first carry out a simple paper chromatography experiment You will have some filter paper and some black ink. Squeeze a drop on the filter paper and leave it until it dries. Then add a few drops of water, slowly. Write down what you observe.

6. Chromatography Next you are going to use ethanol to separate the different colours of some Smarties. The most soluble substance will travel the longest distance When you are finished: • Write a diagram and method • List another solvent you could use apart from ethanol (p.171) • Why can chromatography be useful? (p.171)

7. Plenary • What things do you need to remember when setting up the apparatus?…write down 2 points • Appraise your neighbour’s write-up and question answer