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=Properties of Solid, Liquid & Gas

=Effect of change of Temp, Pressure

=Interconversion of three states of matter


=Other Concepts



Evaporation: The phenomenon of change of a liquid into vapours at any temperature below its boiling point is called evaporation. For example spreaded water on the floor disappears after some time even when the temperature of the surface of the floor is much lower than the boiling point of water.
What are the various factors that affect evaporation?
Various factors that affect evaporation are:

(i) Surface area: By increasing the surface area the rate of evaporation increases and vice versa.
(ii) Temperature: By increasing the temperature the rate of evaporation increases and vice versa.
(iii) Wind Speed: By increasing the wind speed the rate of evaporation increases and vice versa.
(iv) Humidity: : By increasing the humidity the rate of evaporation decreases and vice versa.

How does evaporation cause cooling?
When a liquid keeps on evaporating. The particles of liquid absorb energy from the surrounding to regain the energy lost during evaporation. This absorption of energy from the surroundings makes the surroundings cold.


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