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Eat your greens!

    General science equipment

    This is a great experiment to show that hot water is lighter than cold!

    Ingredients and equipment that you will need

    A potato
    Tincture of iodine from the chemist (WARNING iodine stains like mad).
    Vitamin C tablet or powder or orange or lemon juice

    Method and further information

    Cut up a potato and swill it around in water. Then throw the potato away keeping the water. Add a few drops of tincture of iodine (WARNING iodine stains!). It will go black as the starch in the potato reacts with the iodine.

    Add some vitamin C, lemon juice or orange juice and the colour will clear.

    Fruit and vegetables, containing vitamin C, are incredibly good at getting rid of problem chemicals in the body, which is why a healthy diet includes lots of them.

    Be careful – you should ask an adult to help you with these experiments. Do your experiments in old yoghurt pots, jam jars or bottle tops. Don’t use cups or glasses in case someone thinks it’s a drink.