Question

Which of the following is not true of chemical changes?

A chemical change rarely occurs at the molecular level.
Flammability and decomposition are examples of chemical changes.
Chemical changes involve a rearrangement of atoms to form new substances.
Chemical changes can often be identified by clues such as formation of a gas or a solid and a release of heat.

Answer 1

They rarely occur at molecular levels is incorrect, actually they always occur at molecular levels

Answer 2

Answer: Option (a) is the correct answer.

Step-by-step explanation:

At molecular level there will be need of energy always for breaking or making of chemical bonds. Therefore, a chemical change will always occur at molecular level.

Thus, we can conclude that out of the given options, the statement a chemical change rarely occurs at the molecular level is not true of chemical changes.