Which of the following is not a characteristic of a chemical change?
- AIt is irreversible
- BNew substance is formed
- CNo net change in energy is involved
- DIt involves absorption of energy
- ENone of the above/More than one of the above
Show answer and explanation
Correct answer: (c) No net change in energy is involved
Explanation
A chemical change forms new substances, is usually irreversible, and always comes with an energy change: heat or light is given out or taken in.
So "no net change in energy" is not a feature of a chemical change. Reactions are exothermic (burning) or endothermic (photosynthesis).