Chapter U3.66, Problem 8E

Interpretation Introduction

Interpretation :

This is to be explained how two different water vapor densities are at 100 % humidity.

Concept Introduction :

Saturation of air with water vapor depends on temperature. Relative humidity is the ratio of amount of water vapor to the amount of water vapor required for saturation.

Answer to Problem 8E

Due to different temperature, two different water vapor densities can have 100 % humidity.

Explanation of Solution

With the increase of temperature, amount of water vapor required to saturate certain volume of air increases. So, if the temperature is high for a day, more amount of water vapor is required as compared to a day on which temperature is less. Thus, it is possible that on one day, 100 % humidity corresponds to 1.9 moles of water vapor per 1000 L of air and on another day, 100 % humidity corresponds to 1.0 mole of water vapor per 1000 L of air.

Conclusion

Two different days might have different temperatures. So, two water vapor densities can have 100 % humidity.