2. Solved Papers
  3. AIIMS

AIIMS AIIMS Solved Paper-2015

  • question_answer
    Salts of metals X, Y and Z are electrolysed under identical conditions using same quantity of electricity. It was observed that 4.2 g of X, 5.4 g of Y and 19.2 g of Z were deposited at respective cathode. If the atomic weights of X, Y, Z are 7, 27 and 64 respectively, then their ratio of valencies is

    A) 1 : 2 : 3                 

    B)  1 : 3 : 2

    C) 2:3: 1                                    

    D) 3:2:2

    Correct Answer: B

    Solution :

    Molar ratio of X, Y and \[Z=\frac{4.2}{7}:\frac{5.4}{27}:\frac{19.2}{64}\] \[=0.\text{6}:0.\text{2}:0.\text{3}=\text{6}:\text{2}:\text{3}\] As atomic weight = Equivalent weight x valence Y and number of equivalents is same in all three. Therefore, valency ratio of X, Y and Z is 1: 3 : 2.


You need to login to perform this action.
You will be redirected in 3 sec spinner