which of the following is used to adsorb water ?

Options

A. silica gel
B. Calcium acetate
C. Hair gel
D. Anhydrous `CaCl_(2)`

Answer

To determine which of the given options is used to adsorb water, we can analyze each option based on their properties and common uses.

### Step-by-Step Solution:

1. **Understanding Adsorption**:
- Adsorption is the process by which molecules adhere to the surface of a solid or liquid. In this case, we are looking for a substance that can effectively adsorb water.

2. **Analyzing Each Option**:
- **Silica Gel**:
- Silica gel is a porous and granular form of silicon dioxide. It has a high surface area and strong affinity for water molecules, making it an excellent desiccant (drying agent). It is commonly used to control humidity and adsorb moisture in various applications.
- **Calcium Acetate**:
- Calcium acetate is a salt that is not typically used for moisture adsorption. It is more commonly used in food preservation and as a food additive.
- **Hair Gel**:
- Hair gel is a cosmetic product primarily designed to style hair. It does not have significant moisture-adsorbing properties.
- **Anhydrous CaCl2 (Calcium Chloride)**:
- Anhydrous calcium chloride is a hygroscopic compound, meaning it can absorb moisture from the air. It is often used as a desiccant, but it is not as commonly recognized for this purpose as silica gel.

3. **Conclusion**:
- Among the options provided, **silica gel** is the most effective and commonly used substance for adsorbing water. While anhydrous calcium chloride can also absorb moisture, silica gel is more widely recognized for this specific application.

### Final Answer:
- The correct answer is **Silica Gel**.

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