Page 79 - Active Science 5 Ebook and Activity
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Observation            :    Clear water collects separately in the container and insoluble solid

                                      remains behind in the funnel.
        Conclusion              :    Clear  liquid  or  water  is  called  filtrate  and  the  insoluble  solid
                                      substance left behind is called residue.



        Filtration in Day-to-day Life

          •  Vacuum cleaners keeps away dust particles and germs.

          •  Coffee makers keeps out coffee seeds or grounded coffee particles.

          •  Taps keep away germs and insects.
                                                                                Be Eco-friendly!
          •  Air conditioners trap dust particles.                              Carry a refillable bottle and a

                                                                                mug for beverages.


         2.  Sedimentation and Decantation: In sedimentation, the mixture of impure water
              is allowed to stand undisturbed for some time. The impurities after a while will
              settle down at the bottom of the container. The substance that settles down is called
              sediment. This process is called sedimentation.


            The process by which a liquid is carefully poured out leaving behind the sediment is
              called decantation.


        Activity 6.6
        Aim                      :    To demonstrate the process of
                                      sedimentation
        Materials Required:    Two containers, mud, water
        Procedure                :  •  Take a container.

                                   •  Put some mud in the container
                                      and wait for a few minutes.

                                   •  You will notice that mud has  Sedimentation                     Decantation
                                      settled down at the bottom of
                                      the container slowly. This is called sedimentation.
                                   •  Now  pour  the  water  slowly  and  carefully  into  another  container
                                      without disturbing the mud. This called decantation.
        Observation              :    The insoluble substances such as mud being heavier settle down at
                                      the bottom of the container.
        Conclusion               :    The impurities settle down at the bottom of the container because
                                      they are heavier than water.




         R emoving Soluble Substances from Water
        Soluble substances can be removed from water by evaporation or distillation.


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