Page 1 - 3.LESSON NOTES-(CH-2 WASHING SODA& PLASTER OF PARIS)
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SAI International School
                                                       Class-X

                                               Subject_ Chemistry
                                          Topic- Acids, Bases & Salts
                               Sub Topic- Study of Salts – 4. Washing Soda

                                                                              5. Plaster of Paris
                                                    Lesson notes

                   •  STUDY OF SALTS-

                   1.  Washing Soda  (Common Name)
                                                 OR
                             •  Chemical Name – Sodium Carbonate deca hydrate
                             •  Chemical Formula – Na2CO3. 10 H2O




















                                      Preparation of Washing Soda-
                   •  Washing Soda is prepared from Baking Soda by heating it,
                       followed by Recrystallization.

                   •  It takes place in three steps.

               Step-1           CO2 + H2O + NH3 + NaCl   →    NaHCO3  +  NH4Cl
                                                                                                                            Baking soda         Ammonium chloride
               Step-2           2NaHCO3     --Heat-----→     Na2CO3   +   H2O   +   CO2
                                                Baking Soda                                 Sodium Carbonate


               Step-3           Na2CO3  +   10H2O   --recrystallization-→   Na2CO3 . 10H2O


                                Properties of Washing Soda-
                 1.  It is a white transparent crystalline solid












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