Question

When iron nails are added to an aqueous solution of copper sulphate, a chemical change occurs. Which of the following is/are true about this reaction?

• A. Blue colour of the solution fades
• B. Iron nails become brownish in colour
• C. It is a displacement reaction
• D. Iron nails dissolve completely

Answer 1

Answer: (A), (B), (C)

The correct options are
A

Blue colour of the solution fades

B

Iron nails become brownish in colour

C

It is a displacement reaction

When iron nails are added to an aqueous solution of copper sulphate, a displacement reaction occurs in which iron displaces copper from its solution which leads to fading of the blue colour of solution. After some time, the displaced copper settles down on the iron nails which become brownish in colour. It also reduces the surface available for reaction. So, the iron nails do not dissolve completely.