Cation exchange resin contain large organic molecule with _____ group.

Answer

To answer the question, "Cation exchange resin contains large organic molecules with _____ group," we need to understand the structure and function of cation exchange resins.

### Step-by-Step Solution:

1. **Understanding Cation Exchange Resins**:
- Cation exchange resins are materials used to remove cations (positively charged ions) from solutions, such as hard water. They are typically made of large organic molecules.

2. **Identifying Functional Groups**:
- The large organic molecules in cation exchange resins contain specific functional groups that allow them to interact with cations. The most common functional groups in cation exchange resins are acidic in nature.

3. **Common Functional Groups**:
- The two primary functional groups found in cation exchange resins are:
- **Sulfonic acid group (–SO3H)**: This group is highly effective in exchanging cations because it can release hydrogen ions (H+).
- **Carboxylic acid group (–COOH)**: This group can also release hydrogen ions and participate in cation exchange.

4. **Conclusion**:
- Therefore, the correct answer to the question is: "Cation exchange resin contains large organic molecules with **sulfonic acid or carboxylic acid** group."

### Final Answer:
Cation exchange resin contains large organic molecules with **sulfonic acid or carboxylic acid** group.

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