Which statement describes the relationship between boiling point and pressure for a given refrigerant?

Which statement describes the relationship between boiling point and pressure for a given refrigerant?

• A. Boiling point increases with increasing pressure
• B. Boiling point decreases with increasing pressure
• C. Boiling point is independent of pressure
• D. Boiling point fluctuates randomly with pressure

Answer: (A)

The boiling point is the temperature at which a refrigerant’s vapor pressure equals the surrounding pressure. If you raise that surrounding pressure, the liquid must reach a higher temperature to generate enough vapor pressure, so the boiling point increases. This means for a given refrigerant, higher pressure shifts the boiling point upward, while lower pressure allows boiling at a lower temperature. The other ideas imply no dependence on pressure, a decrease with increasing pressure, or randomness, none of which align with how vapor pressure and temperature relate.

The boiling point is the temperature at which a refrigerant’s vapor pressure equals the surrounding pressure. If you raise that surrounding pressure, the liquid must reach a higher temperature to generate enough vapor pressure, so the boiling point increases. This means for a given refrigerant, higher pressure shifts the boiling point upward, while lower pressure allows boiling at a lower temperature. The other ideas imply no dependence on pressure, a decrease with increasing pressure, or randomness, none of which align with how vapor pressure and temperature relate.