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SAI International School
                                                  Subject-Chemistry

                                             Ch-Atoms and Molecules
                                            Topic-Symbols of elements
                                                    LESSON NOTE


               Atoms:  These  are  the  smallest  particle  of  matter  which  may  or  may  not  have  an
               independent existence and take part in chemical reactions.


               Molecules: These are the smallest particle of matter which can exist independently.
               Atoms:
               The smallest tiny particles of matter which can't be divided further is called atom, i.e., an
               atom is the smallest building block of matter.

               For example: Sodium (Na), Hydrogen (H), Oxygen (O), etc.


               Names of Elements and their Symbols:
               John Dalton in 1808 first used figurative symbols to represent different elements. As you
               can see it is tedious and non-practical hence it was soon abandoned
              IUPAC (International Union of Pure and Applied Chemistry) approves names of
               elements.
              The abbreviation used for lengthy names of elements are termed as their symbols.
              The symbol of an element is formed by writing only the first letter or first letter followed
               by the second or some other letter of English name or Latin name of the element.
              While writing a symbol, the first letter is always capital and the second is always small.
              Symbols used for some common elements are given below:
































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