On a particular hot day, the temperature is 40°C and the partial pressure of water vapor in the air is 38.8 mmHg. What is the relative humidity?

 

On a particular hot day, the temperature is 40°C and the partial pressure of water vapor in the air is 38.8 mmHg. What is the relative humidity?

 

A.

70

B.

62

C.

80

D.

42

Correct answer is A

Relative Humidity=  \(\frac {partial  pressure  of  H2O}{saturated  vapor  pressure  of  H2O}\)×100%

S.v.p. of water at 40°c = 55.3

⇒ Relative Humidity=  \(\frac{38.8}{55.3}\)×100%

Relative Humidity= 70%