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Question
What is boiling? Explain it on the basis of molecular motion?
Solution
BOILING: “The change of liquid to vapours on heating at a constant temperature is called BOILING”
K.E = `1/2`Mv2: more the speed of molecules more is the kinetic energy. Heating of the liquid increases the average kinetic energy of liquid molecules and molecules acquire sufficient K.E. needed to overcome the force of attraction of other molecules. These molecules start leaving the liquid not only at the surface but also near the walls of the containing vessel and bubbles are seen on the walls of the vessel. This causes the agitation in the whole of the liquid and this is called boiling.
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