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DO LIQUIDS CONDUCT ELECTRICITY..??

              There  are  some  important  differences  in  the  conduction  of  electricity  by  solids  (such  as

               metals) and liquids.

              The liquids that conduct electricity are solutions of acids, bases and salts.
               In  solids,  electricity  is  carried  by  electrons  but  in  liquids,  electricity  is  carried  by  the

               positively and negatively charged ions.

              When electricity is passed through a solid, then no chemical change is observed but when
               electric current is passed through a liquid, then a chemical change takes place.

              For e.g., when electricity is passed through a copper wire, no chemical change takes place
               in  it  but  when  electricity  is  passed  through  a  acidified  water  (water  having  high

                                     +
               concentration  of  H   ions),  then  a  chemical  change  takes  place  in  which,  water  is
               decomposed into hydrogen and oxygen gases.

              The liquids which conduct electricity are called Conducting liquids.

              The solutions of acids, bases and salts in water are called as Electrolytes.
              The  chemical  changes  that  take  place  in  conducting  liquids  on  passing  electric

               current through them are called Chemical Effects of Electric Current.



        TO TEST WHETHER A LIQUID CONDUCTS ELECTRICITY OR NOT:


            A.  Testing conduction of electricity in Hydrochloric acid in water:

                     Take a small beaker and fix two iron nails on a rubber cork at about 1 cm apart and
                       place the cork in a beaker.

                     These two iron nails will act as an electrode.

                     Connect the two nails to the two terminals of a battery by including a torch bulb and
                       switch in the circuit.

                     Pour a solution of dilute hydrochloric acid in the beaker carefully.
                     Now  pass  electric  current  through  the  hydrochloric  acid  solution  by  closing  the

                       switch.

                     We will observe that as soon as we switch on the current,the bulb starts glowing.
                     The bulb can glow only if the hydrochloric acid solution taken in the beaker conducts

                       electricity. So the glowing of bulb this case tells us that Hydrochloric acid solution
                       conducts electricity.




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