Page 1 - 3.LESSON NOTES-FACTORS AFFECTING STATES OF MATTER
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SAI International School
                                                       Class-IX

                                                Subject-Chemistry
                                      Topic-Matter in our surroundings
                             Sub topic- Factors affecting the states of matter

                                                  LESSON NOTES
               LATENT HEAT: During the melting of solid, the temperature remains the same. The
               heat gets used up in overcoming the forces of attraction between the particles of
               matter. The heat energy is being absorbed by solid ice without any rise in
               temperature. This heat is regarded to be hidden in the contents of the container and
               is called latent heat.
























               Fig. Heating of ice to convert it into liquid
               It can be further defined as follows:

               The amount of energy needed for the conversion of 1kg of solid to liquid at
               atmospheric pressure at its melting point is known as the latent heat of fusion.
























               Fig. Heating of the liquid to convert it into vapour





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