Question

A molecule contains 18 atoms and undergoes a physical change. How does the physical change affect the total number of atoms of each element? It remains the same. It increases. It changes to zero. It decreases.

Answer 1

It remains the same.

Step-by-step explanation:

Physical changes will not affect the number of atoms in a molecule. Dissolving the substance and melting are physical changes which, if they are reversible, will not affect the chemical composition of the molecule.

In the moment in which the physical change is not reversible the molecules may undergo a chemical change and this it will affect the chemical composition. Sometimes when we try melting organic molecules and we end up carbonizing the compound forming carbon and maybe carbon dioxide and water beside other kind of compound that are formed when an organic compound is burned.