Which of the following is not a chemical reaction?
A. Burning of bush B. Rusting of iron C. decay of bitter leaves D. Dissolution of potassium hydroxide pellets
Correct Answer: D
Explanation
In Bush burning new kinds of matter such as gases and ashes are produced from organic compound; rusting of iron is not a reversible process, decay of bitter leaves produces entirely new substances, hence, they are all chemical changes (reactions). Only dissolution of potassium hydroxide pellets is a physical change, as the process is reversible and no new kind of matter is formed