Samples of four metals A, B, C and D were taken and added to the following solution one by one. The results obtained have been tabulated as follows. 

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Use the Table above to answer the following questions about metals

A, B, C and D.

(i) Which is the most reactive metal?

(ii) What would you observe if B is added to a solution of Copper(II) sulphate?

(iii) Arrange the metals A, B, C and D in the order of decreasing reactivity.

 

Answer

(i)

According to the reactivity series , among the 4 salts given, Zinc Sulphate is the most reactive

  • Since no metals react with it, we consider the next most reactive solution, Iron (II) Sulphate .
  • Since only B is able to displace Iron from Iron (II) Sulphate, it is the most reactive among A,B,C,D

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(ii) What would you observe if B is added to a solution of Copper(II) sulphate?

B is more reactive than Fe, which in turn is more reactive than Cu.

And so, B will displace Cu from its salt solution.

 

(iii) Arrange the metals A, B, C and D in the order of decreasing reactivity.

Let us go in order of most reactive to least reactive salt solutions.

  • Zinc solution is the most reactive salt solution here. But no metal reacts with it
  • B is the most reactive element as it is able to displace Iron from its salt solution .
  • A is able to displace copper from its salt solution.
  • C is able to displace Silver from its salt solution.
  • D is the least reactive element, since it does not react at all .

 

So,  The reactivity series in decreasing order is given as

B>A>C>D

 

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CA Maninder Singh is a Chartered Accountant for the past 14 years and a teacher from the past 18 years. He teaches Science, Economics, Accounting and English at Teachoo