Various Indicators and Their Color Changes in Acidic and Basic Medium

Indicators are substances that change color in response to pH levels, helping to identify whether a solution is acidic or basic. Below is a list of commonly used indicators, their pH range, and their color change in acidic and basic media.

Various Indicators and Their Color Changes in Acidic and Basic Medium

1. Methyl Violet

🔹 pH Range: 0.0 – 1.6
🔹 Acidic Medium: Yellow
🔹 Basic Medium: Violet

2. Bromophenol Blue

🔹 pH Range: 3.0 – 4.6
🔹 Acidic Medium: Yellow
🔹 Basic Medium: Blue

3. Methyl Orange

🔹 pH Range: 3.1 – 4.4
🔹 Acidic Medium: Red
🔹 Basic Medium: Yellow

4. Methyl Red

🔹 pH Range: 4.4 – 6.3
🔹 Acidic Medium: Red
🔹 Basic Medium: Yellow

5. Litmus

🔹 pH Range: 5.0 – 8.0
🔹 Acidic Medium: Red
🔹 Basic Medium: Blue

6. Bromothymol Blue

🔹 pH Range: 6.0 – 7.6
🔹 Acidic Medium: Yellow
🔹 Basic Medium: Blue

7. Phenolphthalein

🔹 pH Range: 8.3 – 10.0
🔹 Acidic Medium: Colorless
🔹 Basic Medium: Pink

8. Alizarin Yellow

🔹 pH Range: 10.1 – 12.0
🔹 Acidic Medium: Yellow
🔹 Basic Medium: Red

Summary Table of Indicators and Their pH Ranges

Key Points to Remember:

✅ Methyl Orange is commonly used in acid-base titrations.
✅ Phenolphthalein is useful for identifying strong bases.
✅ Litmus Paper is a general acid/base test: red in acid, blue in base.
✅ Bromothymol Blue is often used to test for neutral pH (green at pH 7).

💡 Application in Chemistry:

• These indicators are widely used in laboratories for acid-base titrations, water quality testing, and medical diagnostics.
• Choosing the right indicator depends on the pH range of the reaction.

This information is essential for students, pharmacists, chemists, and healthcare professionals. 🚀