Show your child how to create a concoction of simple household ingredients that changes colours as acids and bases are added! This magic mixture is called a “pH indicator,” a chemical compound that is added to a solution in order to determine its acidity or basicity visually. While many items (such as cabbage juice) have this ability, this mixture of turmeric and rubbing alcohol possesses the unique trait of being able to change back to its original colour. Science has never been this fun!
What You Need:
❑ Bowl
❑ 1/4 cup water
❑ 1/4 cup vinegar
❑ 1/2 teaspoon turmeric
❑ 1/2 cup rubbing alcohol
❑ 1 teaspoon baking soda
❑ Clear drinking glass
What You Do:
- Help your child combine the turmeric and rubbing alcohol in the bowl.
- Combine the baking soda and water in the glass.
- Help your child to pour a sufficient amount of the turmeric/alcohol combination into the glass to effect a colour change. Ask him to observe the reaction. What colour was produced?
- Help your child pour the vinegar into the glass.
What’s Going On?
Adding the pH indicator to the basic solution should have turned it red. Adding an acid (vinegar) made it foam and revert to its original yellow colour.
