Examkin

Soru

Zorluk: ZorVapour Pressure, Boiling, Evaporation, and Relative Humidity

If a fixed mass of unsaturated air in a closed container is cooled at constant total pressure, its relative humidity increases until it reaches the dew point; upon cooling further below the dew point, condensation occurs such that the relative humidity remains at 100% while the saturated vapour pressure continues to decrease.

Cevap: Cevap

Cevap

The statement is True.
Cooling unsaturated air reduces its maximum moisture-holding capacity (SVP). Before saturation, actual vapour pressure is fixed, so relative humidity rises to 100% at the dew point. Continuous cooling past this point forces condensation, decreasing the actual vapour pressure alongside the SVP to keep the air continuously saturated at 100% relative humidity.

Adım Adım Çözüm

1
Analyze the relationship between cooling and relative humidity for unsaturated air.
As temperature decreases, the saturated vapour pressure (SVP) decreases while the actual partial vapour pressure remains constant, causing relative humidity (actual VP / SVP × 100%) to increase.
Relative humidity is inversely proportional to the saturated vapour pressure at a fixed moisture content.
2
Identify the state reached when relative humidity reaches 100%.
The air reaches saturation at the dew point temperature where actual vapour pressure equals SVP.
By definition, the dew point is the temperature at which water vapour in air begins to condense.
3
Determine the thermodynamic behavior during continuous cooling below the dew point.
Excess vapour condenses into liquid water, decreasing actual vapour pressure to continuously match the lower SVP at each reduced temperature.
Air cannot maintain an unsaturated or supersaturated equilibrium state in the presence of condensate, keeping relative humidity locked at 100%.

Anahtar Kavram

Vapour saturation, dew point determination, and condensation mechanics during air cooling.
Tahmini Süre:1m 30s
Bu soruyu puanla

Konular

Vapour Pressure, Boiling, Evaporation, and Relative Humidity

Bu konudan daha fazla soru