The boiling point of water at high altitude is low, because

Options

A. the temperature is low
B. the atmospheric pressure is low
C. the temperature is high
D. the atmospheric pressure is high

Answer

To solve the question regarding why the boiling point of water at high altitude is low, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding Boiling Point**: The boiling point of a substance is the temperature at which its vapor pressure equals the external atmospheric pressure. At this point, the liquid turns into vapor.

2. **Effect of Altitude on Atmospheric Pressure**: As altitude increases, the atmospheric pressure decreases. This is because there is less air above you exerting pressure at higher elevations.

3. **Relation Between Atmospheric Pressure and Boiling Point**: Since the boiling point is dependent on atmospheric pressure, when the pressure decreases, the temperature at which water can boil also decreases. This means that water will boil at a lower temperature at high altitudes compared to sea level.

4. **Conclusion**: Therefore, the boiling point of water at high altitude is low because the atmospheric pressure is low.

### Final Answer:
The boiling point of water at high altitude is low because the atmospheric pressure is low.

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