Natural Indicator Around Us
Key Notes :
1. Definition of Indicators
- Indicators are substances that change color when added to acidic or basic solutions, helping to determine the pH of a substance.
2. Types of Indicators
- Natural Indicators: Indicators derived from natural sources like plants. They are non-toxic and environmentally friendly.
- Synthetic Indicators: Man-made indicators like phenolphthalein and methyl orange.
3. Common Natural Indicators
- Litmus: Extracted from lichens, litmus turns red in acidic solutions and blue in basic solutions.
- Turmeric: Turmeric powder turns red in basic solutions but remains yellow in acidic or neutral solutions.
- China Rose (Hibiscus): The extract turns acidic solutions dark pink/red and basic solutions greenish.
- Red Cabbage: Red cabbage juice turns red in acidic solutions and green in basic solutions.
4. Use of Natural Indicators
- Natural indicators are used in laboratories and at home to test the acidity or basicity of substances like vinegar, baking soda, lemon juice, and soap.
5. Advantages of Natural Indicators
- They are eco-friendly, non-toxic, and easily available.
6. Applications in Daily Life
- Testing soil pH for gardening.
- Checking the pH of water in swimming pools.
- Determining the acidity of food items.
Let’s practice!
