MATERIALS: Cornflour Water Food colouring A bowl A spoon INSTRUCTIONS: - Put two glasses of cornflour into the bowl. - Add a glass of water and four or five drops of food colouring. - Mix everything. - Make a ball in your hands. Is it a solid or a liquid? - Hold it up in your hand. Is it a solid or a liquid?
The mixture is solid and liquid at the same time. Cornflour is made of lots of long tiny particles (molecules) which don't dissolve in water but spread themselves out. When you make a ball in your hands the particles join together and it looks like a solid; but when you hold it up the particles slide over each other and it looks like a liquid.
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