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SAI International School
                                                       Class-VII
                                                Subject-Chemistry
                                         Topic-Acids, Bases and Salts
                                      Sub-topic-Salts and its properties



                                                  LESSON NOTE




               SALTS

               Salts are substances that are produced as a result of neutralisation

               reaction between an acid and a base. This can be written in a word
               equation as:


               Acid + Base    Salt + Water

               The name of a salt has two parts. The first part is the name of the metal
               which replaces the Hydrogen of the acid. The second part is the radical

               of the acid. For example, in the salt Magnesium sulphate, Magnesium is
               the first part which has replaced hydrogen from the acid and Sulphate is
               the radical from the acid, Sulphuric acid.


               Methods of preparation of salts:


                   1.  By neutralisation reaction between an acid and a base.
                       For example, Hydrochloric acid (acid) reacts with Sodium
                       hydroxide (base) to form Sodium chloride (salt) and water.
                       HCl + NaOH  NaCl + H O
                                                     2
                   2.  They can also be prepared by a reaction between an active metal
                       and an acid.
                       For example, the metal Zinc (Zn) can react with Hydrochloric acid

                       (HCl) to produce the salt Zinc chloride (ZnCl ) and Hydrogen (H )
                                                                                                     2
                                                                             2
                       gas.
                       Zn + 2HCl  ZnCl  + H
                                                    2
                                              2



               Properties of Salts:

               Salts generally have the following properties:


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