Page 5 - 3. Lessson Notes- Ch-3 Chemical properties of Metal & Non metals -PDF
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1.  Method of collection of Hydrogen gas-
                        Downward displacement of water.
                   2.  What property of Hydrogen gas is evident in this experiment, by this method
                       of collection?
                       Hydrogen gas is –     1. lighter than water
                                                           2.Insoluble in water.

                       3. Give a test to identify the presence of Hydrogen gas-

                A burning splinter, when brought near the gas, gets extinguished with a pop sound.


                       •  Reaction of metals with Dilute Acids_  (Examples):

               Exception-
                       •  Hydrogen gas is not evolved when a metal reacts with nitric acid.
                       •  Reason-  It is because HNO3 is a strong oxidizing agent.
                           It oxidizes the Hydrogen produced, to water and itself gets reduced to
                          any of the nitrogen oxides (N2O, NO,NO2).
                       •  Exception- But magnesium (Mg) and manganese (Mn) react with very
                          dilute HNO3 to evolve H2 gas.
                       •  Examples-
















































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