Why does the colour of copper sulphate solution change when an iron nail is dipped in it?

 

Answer

Iron is a more reactive metal than copper .

(Since it lies above copper in the reactivity series)

 

K

Na

Ba

Ca

Mg

Al

Zn

Fe

Ni

Sn

Pb

H

Cu

Hg

Ag

Au

Pt

 

Copper Sulphate solution is blue .

When a piece of iron nail is placed in Copper Sulphate solution,

Iron Sulphate and Copper is formed as shown below

 

Fe(s) + CuSO 4 (aq) → FeSO 4 (aq) + Cu(s)  

 

Hence, the colour of the solution turns from blue to transparent , because Fe displaces Cu from CuSO 4 (Copper Sulphate) to form FeSO 4 (Ferrous sulphate) , which is transparent.

  1. Class 10
  2. Chapter 1 Class 10 - Chemical Reactions and Equations (Term 1)

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CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo