Question

The colour of the solution observed after about 1 hour of placing iron nails in copper sulphate solution is ______.

पर्याय

• Blue

• Pale green

• Yellow

• Reddish brown

Answer 1

The colour of the solution observed after about 1 hour of placing iron nails in copper sulphate solution is pale green. 

Explanation:

When iron nails are placed in CuSO₄ solution, a displacement reaction occurs. When iron displaces copper from copper sulphate, it produces iron(II) sulphate, a pale green compound. After approximately 1 hour, the solution will turn pale green due to the formation of iron(II) sulphate.

\[\ce{\underset{(Grey)}{\underset{Iron}{Fe_{(s)}}} + \underset{(Blue)}{\underset{Copper sulphate I}{CuSO4_{(aq)}}} -> \underset{(Pale green)}{\underset{Iron sulphate}{FeSO4_{(aq)}}} + \underset{(Reddish brown)}{\underset{Copper}{Cu_{(s)}}}}\]