Question

Draw and explain the process involved for measuring humidity. ​

Answer 1

Explanation:

HUMIDITY MEASUREMENT

Richardson, J.F.

DOI: 10.1615/AtoZ.h.humidity_measurement

The humidity of a gas may be measured by a variety of techniques. Some are based on the determination of the partial pressure of vapor in the gas (e.g., dew point determination); the relationship between humidity and partial pressure is given in the entry entitled Humidity. Measurements of wet and dry bulb temperatures involve the use of the psychometric chart (see Air Conditioning). There are other methods which depend on the influence of humidity on the physical properties and behavior of various substances.

Measurement of Dew Point

This is the determination of the temperature at which the partial pressure of the water vapor is equal to its saturation value. It involves gradually reducing the temperature of a mirror, or other highly polished surface, within the gas and determining the temperature at which condensation is first observed. This temperature is known as the dew point. The partial pressure of water in the gas is, therefore, that of saturated gas at this temperature. Therefore, the required value of humidity can be obtained from the saturation curve on the psychrometric chart.