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CT – 2
                                                                                                D – 1
                                                                                                A – 1
                                                                                                T – 1
                                                                                                S = ½
                                                                                                       P = 1
                                                                                                C = 1








             (ii) 1  = 0.00510 √½    From the graph and must be shown. Showing. √½
                                       t

                           t =   1  √½   = 196.5 seconds. √½
                           0.00510
                      (iii) Mg (s)    + H 2SO 4(aq)                            MgSO 4(s)  + H 2(g) √½
                           1   :      1                                   With correct physical state.
                        (iv) Moles of Mg = 0.12 √½   = 0.005 moles √½
                                         24                                                   1mk
                          Moles of H 2SO 4 used = 0.005 moles      (1 : 1)
                         (v) Increase in length of M of ribbon results in decrease in   1
                                                                                     t     √½

                          This is done to gradual decrease in the concentration of the acid. √½

          Table II

                  Titration                             I          II                   III
                                           3
                  Find burette reading (cm )            15.3       30.5                 45.7
                  Initial burette reading               0.0        15.3                 30.5
                                                 3
                  Volume of solution B used (cm )       15.3       15.2                 15.2
                                                                                                CT = 1
                                                                                         D = 1
                                                                                                AC = 1
                                                                                                PA = 1
                                                                                                TA = 1
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