Which of the following is not a chemical method to purify water ?

Options

A. Use of bromine
B. Use of chlorine
C. Use of hydrogen peroxide
D. Filtration

Answer

To determine which option is not a chemical method to purify water, we can analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Methods Listed**: We need to look at the options given for purifying water and identify whether they are chemical methods or not.

2. **Evaluate Each Option**:
- **Option 1: Use of Bromine**: Bromine is a chemical element and is used as a disinfectant in water treatment. Therefore, this is a chemical method.
- **Option 2: Use of Chlorine**: Chlorine is widely used for disinfecting water and is a chemical method of purification.
- **Option 3: Use of Hydrogen Peroxide (H2O2)**: Hydrogen peroxide is also a chemical compound used for water purification, making this a chemical method.
- **Option 4: Filtration**: Filtration is a physical method of purifying water. It involves passing water through a filter to remove impurities and does not involve any chemical reactions.

3. **Conclusion**: Based on the evaluation, the option that is not a chemical method to purify water is **Option 4: Filtration**.

### Final Answer:
**Option 4: Filtration** is not a chemical method to purify water.

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