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Evaporation. The change from liquid to vapour (gas) is called vaporization or evaporation. The gaseous form of a substance which i s a liquid or solid at room temperature & pressure is called vapour.
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Evaporation The change from liquid to vapour (gas) is called vaporization or evaporation. The gaseous form of a substance which is a liquid or solid at room temperature & pressure is called vapour. As vapour particles move randomly about, they collide with other particles as well as the sides of the container they are in.
These collisions create a certain amount of pressure on the sides of the container. This pressure is known as vapour pressure of that substance.
What is the difference between boiling and evaporation? Evaporation occurs only at the surface of liquids. When a liquid boils, it changes to a gas throughout the whole liquid. We generally consider a liquid boiling if we see bubbles. These bubbles are vapour forming below the surface of the liquid.
Vaporization of a Liquid in a Closed Container Even if a container is closed, a liquid will continue to vaporize. However the vapour particles cannot escape into the atmosphere. Eventually, some particles will collide with the surface of the liquid & condense back into liquid state. After some time, the rate of liquid particles evaporating will equal the rate of vapour particles condensing. This is called DYNAMIC EQUILIBRIUM