Question

In reaction A Zinc was added to solution of copper salt the blue colour of solution disappear

In reaction B zinc sulphate solution was added to blue copper(II) chloride solution the colour of solution remains blue.

(i) what are the types of reactions occurring(if any) in each case ? 1

(ii) Why does the blue colour persists in second case? 1

(iii) Write the balanced equations for the above observations? 2 [4]

B) X, Y and Z are three metals. Y when added to salt solution of X , change of colour was seen but when added to salt solution of Z no change was seen.

Will there be any change if Z is added to salt solution of X ? Explain the reason. [1]

Answer 1

Answer:

on adding zinc to CuSO

4

​

 solution, zinc displaces copper from copper sulphate & forms zinc sulphate solution because zinc is more reactive metal which displaces less reactive metal from its solution.

This is indicated by a colour change from blue to colourless.

CuSO

4

​

 solution has a blue colour while ZnSO

4

​

 solution is colourless.

Zn+CuSO

4

​

→ZnSO

4

​

+Cu

Explanation: