Turmeric indicator paper

Indicator paper

You could make a really striking image using the techniques in this experiment.

Ingredients and equipment that you will need

Two rigid plastic (NOT glass) cups
Hot water
Kitchen roll

Method and further information

Mix a teaspoonful of turmeric or surgical spirit. (Be careful it stains)

Dip blotting paper into this or paint the blotting paper with it. Leave to dry on some paper.

When it has dried completely dip it into a spoonful of soda crystals dissolved in water and it will go brick red. Dip it into vinegar and it goes back to yellow again

Many plants like turmeric are sensitive to acids (anything that tastes sour) and alkalis (things that you clean with). This is one reason why acid rain is a problem.

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.