Question

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

• A. Blue
• B. Pale green
• C. Yellow
• D. Reddish brown
  {5pt}

Hint:

In displacement reactions, a more reactive metal can displace a less reactive metal from its salt solution.

Answer 1

The Correct Option is B

Step 1: Reaction of iron nails with copper sulphate. When iron nails are placed in copper sulphate solution, a displacement reaction occurs, where iron displaces copper from its salt, forming iron(II) sulfate and copper. 
Step 2: Conclusion. The resulting colour of the solution changes to pale green, indicating the formation of iron(II) sulfate.