Answer:
Nails rusting over time as they are exposed to oxygen
Explanation:
New substance with new property is formed
It have also changed the chemical property of the substance
It is difficult to reverse the change etc...
On the change in potential energy
Answer:
<em>1</em><em>. </em><em>A body is said to be at rest if its position does not change with respect to its surroundings.</em>