Which statement defines the dew point temperature?

Which statement defines the dew point temperature?

• A. It is the temperature at which moisture will condense from the air
• B. It is the temperature at which air becomes humid
• C. It is the boiling point of water
• D. It is the temperature at which air dissolves water vapor

Answer: (B)

Dew point is the temperature to which air must be cooled for water vapor to reach saturation and begin condensing at the current pressure. When air is cooled to this temperature, it can no longer hold all the moisture, so droplets form as condensation occurs. That’s why describing dew point as the temperature at which moisture will condense from the air best captures its meaning. Humidity describes how much water vapor is present, not the temperature at which condensation starts; the boiling point is a fixed property of liquid water at a given pressure and isn’t about atmospheric condensation; and dissolving water vapor isn’t how condensation works in the air.

Dew point is the temperature to which air must be cooled for water vapor to reach saturation and begin condensing at the current pressure. When air is cooled to this temperature, it can no longer hold all the moisture, so droplets form as condensation occurs. That’s why describing dew point as the temperature at which moisture will condense from the air best captures its meaning. Humidity describes how much water vapor is present, not the temperature at which condensation starts; the boiling point is a fixed property of liquid water at a given pressure and isn’t about atmospheric condensation; and dissolving water vapor isn’t how condensation works in the air.