Final answer:
Electrons affect the structure of a molecule by playing a role in chemical bonding. They are involved in the formation of chemical bonds between atoms, which determines the shape and stability of the molecule.
Step-by-step explanation:
The structure of a molecule is affected by electrons because electrons play a significant role in chemical bonding. Electrons are negatively charged particles that orbit the nucleus of an atom. When atoms come together to form a molecule, the electrons are involved in the formation of chemical bonds between the atoms.
For example, in covalent bonding, atoms share electrons, which can result in the formation of single, double, or triple bonds. The arrangement and distribution of electrons determine the shape and stability of the molecule.