Question

Which statement about boiling point is FALSE?

Answer 1

Answer: The boiling point of water is an absolute constant

Explanation:

The boiling point of a compound is NOT an absolute constant. This is because at certain conditions such as a change in altitude, the boiling point of a compound changes.

As temperature increases, evaporation increases and vapour pressure increases. Compounds boils when vapour pressure equal to the atmospheric pressure.

At higher altitudes, atmospheric pressure is decreses.

When atmospheric pressure is decresed, the vapour pressure of the compound is lowered to reach boiling point. Therefore, the temperature needed for vapour pressure to equal atmospheric pressure is lower. The boiling point is lower at higher altitude.

Hence boiling point depends on atmospheric pressure