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.
