Page 1 - 3. Lesson Note-Difference between Elements and Compounds
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SAI International School
                                                  Subject-Chemistry

                                           Ch-Is Matter around us pure?
                     Topic- Difference between elements compounds and mixtures
                                                    LESSON NOTE


               Sl.     Differentiating      Element                          Compound
               No.     Property

               1       Definition           Elements are pure                Compound are pure substances
                                            substances which are             which are formed by two or more
                                            composed of only one type        different types of elements that are
                                            of atom.                         united chemically in fixed
                                                                             proportions.


               2       Total Numbers        There are nearly 118             Compounds are almost endless.
                                            elements (at present) of
                                            which nearly 94 occur
                                            naturally on Earth.

               3       Types                Elements are classified as       Compounds are classified according
                                            either metals, nonmetals or      to their bonds which can be ionic,
                                            metalloids.                      molecular or metallic.

               4       Examples             Some of the examples of          A few examples of compounds are
                                            elements are Iron, Copper,       NaOH, NaCl, HCl etc.
                                            Gold, etc.

               5       Representation       Elements are represented         Compounds are represented by
                                            by symbols and numbers.          their chemical formula. For example,
                                            For example, Sodium is           salt is represented by the formula
                                            represented by Na.               NaCl.
               Difference Between Compounds and Mixtures


             Sl.     Differentiating       Compound                          Mixture
             No.     Property


                                           Compound are substances           Mixtures are substances that
                                           which are formed by               are formed by physically
             1       Definition
                                           chemically combining two or       mixing two or more
                                           more elements.                    substances.
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