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SAI INTERNATIONAL SCHOOL

                                                    CLASS - VIII

                                              Subject – CHEMISTRY

                       Chapter – CHEMICAL EFFECTS OF ELECTRIC CURRENT

                          TOPIC – Electrolytes and It Types, Electrical Circuit


                                                  LESSON NOTES



        ELECTROLYTES and ITS TYPES:

              The liquids which conduct electricity are called as Conducting Liquids.

              When  electric  current is  passed  through  conducting liquids,  then  chemical  changes  take
               place.

              Thus,  a  substance  that  dissociates to produce  ions  (cations  &  anions) in  solution,

               when  dissolved  in  water,  and  has  an  ability  to  conduct  electricity  is  called
               asElectrolyte.

              An electrolyte is a substance that dissociates in water into charged particles called ions.
              A conducting liquid or electrolyte contains both, cations and anions. And, the flow of these

               ions conduct electricity through the electrolyte.

              The solutions of acids, bases and salts in water are electrolytes.
              Examples of electrolytes:

               Acids – H 2SO 4,HNO 3, HCl, H 3PO 4
               Bases – NaOH, KOH, NH 4OH, Ca(OH) 2

               Salts – NaCl, CuSO 4
              A substance that will not dissociate to produce ions (cations &  anions) in solution, when

               dissolved in water, will not be able to conduct electricity, and is called asNon-Electrolyte.


              Electrolytes are basically of two types:

                   a)  Strong Electrolytes: (Good conductor of electricity)

                            Electrolyteswhich  in  their  aqueous  solution  get  completely  ionised  (or)
                              dissociated to form cations and anions, and can conduct electricity very well.

                   b)  Weak Electrolytes: (Poor conductor of electricity)
                            Electrolyteswhich in their aqueous solution getpartially ionised (or) dissociated

                              to form cations and anions, and can conduct electricity to lesser extent.






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