1. What is Fairy Liquid really for?Fairy Liquid

2. What happens when you mix oil and water? Oil and water can’t mix, so you form two layers. We call these substances ‘immiscible’ Is there any way of forcing the two layers to mix?

3. Using an emulsifier If you add an emulsifier to a mixture of oil and water, it can force the two ‘hating’ liquids to mix! You have formed a thick, stable emulsion – like icecream!

4. You need: Oil Water An emulsifier To make an emulsion: e.g. mayonnaise Oil Vinegar Egg yolk

5. You need: Oil Water An emulsifier To make an emulsion: But how does it work…? e.g. washing up! Grease Hot water Fairy liquid!

6. (e.g. the egg yolk or the fairy liquid)

12. But after a while, when two droplets collide, they will merge to form a larger droplet. Eventually the emulsion will separate back into two layers. The longer this takes, the more stable the emulsion was.

13. Task 1.Name an emulsion (F). 2.Name an emulsifier (F). 3.Explain how an emulsion is formed (H).

14. Explain what happens when an emulsifier is added to a mixture of oil and water. Key words: Water hating, water liking, tail, head, oil, water Explain what happens to the micelles when the emulsifier is used up. Key words: Micelles/droplets, repel, spread, emulsion Explain what happens to the micelles after some time Key words: collide, stick/merge, larger droplet Explain what will happen to the mixture when most of the droplets have merged Key words: layer, separate, (density) Predict what will happen to two emulsions where you have added more emulsifier in one than the other Label the diagram of an emulsifier molecule