Relative humidity of a sealed flask of air can be changed by changing the air s temperature or by

a. shining light on the flask.

b. adding or removing water vapor.

c. bringing the flask to a different latitude.

d. adding or removing particles of soil.

Adding or removing water vapor. The correct option is B.

Explanation:

Relative humidity is the amount of water vapour present in the air the greatest amount possible at the same temperature it can hold. Relative humidity is expressed in percentage. It depends on:

- Temperature

- pressure and

- water vapour.

At higher temperature in a given specific and constant amount of moisture, the lower the relative humidity will be. Also, at lower temperature in a given specific and constant amount of moisture, the higher the relative humidity.

Also if the amount of water vapour in the air increases, the relative humidity increases, and if the amount of water vapour decreases, the relative humidity will also decrease.

Therefore relative humidity of a sealed flask of air can be changed by adding or removing water vapour.