Study the experimental setup shown in the diagram and answer the following questions: 
 
Nihal perfomed single displacement reactions using different metals and salt solutions. Observe the image below and answer the questions.
 
 pic9.png
 Reaction between metal and metal salt solution
 
i. Write a chemical equation for the chemical reaction involved.
 
ii. What change is observed when iron nail is added to copper sulphate solution? Explain