Antifreeze are the substances which

Options

A. Stop freezing
B. Decreases freezing point
C. Increases freezing point
D. Melt the ice

Answer

**Step-by-Step Solution:**

1. **Understanding Antifreeze:**
- Antifreeze agents are substances that are added to a solvent (usually water) to lower its freezing point. This prevents the solvent from freezing under low-temperature conditions.

2. **Identifying the Options:**
- The question provides four options regarding the function of antifreeze agents:
- Option A: Stop freezing
- Option B: Decrease the freezing point
- Option C: Increase freezing point
- Option D: Melt the ice

3. **Analyzing Each Option:**
- **Option A (Stop freezing):** This is not entirely accurate as antifreeze does not stop freezing; it lowers the temperature at which freezing occurs.
- **Option B (Decrease the freezing point):** This is correct. Antifreeze agents work by lowering the freezing point of the solvent.
- **Option C (Increase freezing point):** This is incorrect as antifreeze agents do not increase the freezing point.
- **Option D (Melt the ice):** This is also not correct as antifreeze does not melt ice; it prevents the formation of ice by lowering the freezing point.

4. **Conclusion:**
- Based on the analysis, the correct answer is **Option B: Decrease the freezing point**.

5. **Application of Antifreeze:**
- Antifreeze is commonly used in car radiators to ensure that the coolant does not freeze in cold temperatures, allowing the engine to operate efficiently.

**Final Answer:**
Antifreeze agents are substances that **decrease the freezing point** of a solvent (Option B).

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