Here's why:
* Atoms are the basic building blocks of matter. They have a neutral charge when they have an equal number of protons (positive charge) and electrons (negative charge).
* Molecules are formed when two or more atoms bond together. The bonds can be ionic (transfer of electrons) or covalent (sharing of electrons). Regardless of the bonding type, the molecule as a whole will have a neutral charge if the total number of protons and electrons within the molecule is equal.
Let me know if you have any other questions!