How to Make a Liquid PH Indicator

Cooks use turmeric in their curries; home scientists can use turmeric as a pH indicator.

If you're a fan of Indian curries, you know all about turmeric. Turmeric is the spice that gives curry its characteristic color and taste. In addition to being a flavorful spice, turmeric has medicinal uses. For almost 4,000 years, Chinese and Ayurvedic medicine have used turmeric (Curcuma longa) to reduce inflammation, or swelling. Turmeric in solution also makes a useful pH indicator, turning yellow in an acidic solution and red in a basic (alkaline) solution.

Things You'll Need

• Turmeric
• Rubbing alcohol
• Plastic cup or laboratory beaker
• Measuring tablespoon
• Measuring teaspoons
• Plastic spoon or glass stirring rod

Instructions

1. Find turmeric in the spice section of any grocery store. Buy a bottle of rubbing alcohol from any grocery store or drugstore.

2. Measure 4 tbsp. of the rubbing alcohol into a plastic cup or laboratory beaker.

3. Measure 1/4 tsp. of the turmeric and add to the rubbing alcohol in the plastic cup or laboratory beaker.

4. Stir the turmeric and alcohol mixture with a plastic spoon or glass stirrer. Use this liquid as a liquid pH indicator. Add the substance you wish to test to this liquid.

References

• University of Maryland Medical Center: Turmeric
• biologyjunction.com: Making pH Indicators
• ilovebacteria.com: Do Try This at Home

Resources

• Read this Article in Spanish