Answer the given question below:
 
1.  Keerthi is provided with three iron nails, each dipped in oil, water and vinegar. Which iron nail will not rust, and why?
 
i.  What is the colour of the rust?
 
ii. Three iron nail dipped in oil, water and vinegar. Which iron nail will not rust? Explain.
Reason:
 
iii. Write the word equation for rusting.