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

                                                Subject-Chemistry
                                      Topic-Matter in our surroundings
                                     Sub topic- Different states of matter

                                                  LESSON NOTES

                             Solid                           Liquid                          Gas
                 Constituent particles are       Constituent particles are        Constituent particles are
                 very closely packed.            less closely packed.             far apart from each other.
                 Force of attraction between     Force of attraction between      Force of attraction
                 particles is very strong.       particles is less strong.        between particles is
                                                                                  negligible.

                 Force of attraction between     Kinetic energy between           Particles have maximum
                 particles is very strong.       particles is more than that in  kinetic energy.
                                                 solids.

                 Have definite shape and         Do not have definite shape       Neither have definite
                 volume.                         but definite volume.             shape nor definite
                                                                                  volume.

                 Have high density and and       Density is lower than solids     Density is least and can
                 can not be diffused.            and can diffuse.                 easily diffuse.
                 Incompressible.                 Almost incompressible.           Highly compressible.



               Microscopic Explanation for Properties of Solids
               1. Solids have a definite shape and a definite volume because the particles are
               locked into place.
               2. Solids do not flow easily because the particles cannot move/slide past one
               another.
               3. Solids are not easily compressible because there is little free space between
               particles.
               Microscopic Explanation for Properties of Liquids
               1. Liquids are not easily compressible and have a definite volume because there is
               little free space between particles.
               2. Liquids have an indefinite shape because the particles can slide past one another.
               3. Liquids flow easily because the particles can move/slide past one another.
               Microscopic Explanation for Properties of Gases
               1. Gases are easily compressible because there is a great deal of free space
               between particles
               2. Gases flow very easily because the particles randomly move past one another.
               3. Gases have an indefinite shape and an indefinite volume because the particles
               can move past one another.





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