Question

If a sample of air contains 1 g/kg of water vapor and has a relative humidity of 25 percent at -5 degrees Celsius how much water vapor does it need to contain to be saturated?
A) 2 g/kg

B) 1 g/kg

C) 4 g/kg

D) 3 g/kg

Answer 1

Answer:

Option C

Explanation:

As we know that

Relative humidity (RH) is defined as the ratio of amount of water vapor present in a given sample of air to the maximum amount of water that can be  absorbed by the same sample of air to attain saturation  at a particular temperature .

Thus,

$RH = \frac{X}{Y}$

Where X represents the current amount of water vapor present in a given sample of air

and Y represents the maximum amount of water that can be  absorbed by the same sample of air to attain saturation  at a particular temperature

Substituting the given values in above equation we get -

$0.25 = \frac{1 g/Kg}{Y} \\Y = \frac{1 g/Kg}{0.25} \\Y = 4 g/Kg$

Hence, option C is the correct answer