question_answer

    There are 3 unknown metals ? A, B and C. C displaces B from its oxide while with oxide of A, there is no reaction. Give the reactivity order of A, B and C.

Answer:

                    C displaces B from its oxide, therefore, C is more reactive than B. There is no reaction when C is treated with oxide of A or C does not displace A from its oxide. So, A is more reactive than C. Thus, the reactivity order is B < C < A.