* Physical Properties: These are characteristics of a substance that can be observed or measured without changing the substance's chemical composition. Examples include color, density, melting point, boiling point, etc.
* Boiling Point: The boiling point of a liquid is the temperature at which its vapor pressure equals the surrounding atmospheric pressure, causing it to change from a liquid to a gas.
* Atmospheric Pressure: Atmospheric pressure decreases with altitude. This means that the pressure on top of a mountain is lower than at sea level.
* Effect on Boiling Point: Since the boiling point is dependent on atmospheric pressure, water boils at a lower temperature on a mountain because the air pressure is lower.
Therefore, the lower boiling point of water on a mountain is a physical property because it relates to a measurable characteristic (boiling point) that is influenced by external conditions (atmospheric pressure) without changing the chemical composition of water.
