Which statement best describes the difference between a neutral atom and an ion?

• A. An atom contains only protons and neutrons, while an ion contains protons, neutrons, and electrons.
• B. An atom is electrically neutral (equal numbers of protons and electrons), while an ion has a net charge because it has gained or lost electrons.
• C. An atom and an ion differ only in the number of neutrons; ions have more neutrons than atoms.
• D. An atom always has more protons than electrons, while an ion always has more electrons than protons.

Answer: (B)