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)

Verified step by step guidance

1. Step 1: Understand the basic structure of an atom. An atom consists of protons, neutrons, and electrons. Protons carry a positive charge, electrons carry a negative charge, and neutrons are neutral.
2. Step 2: Recognize that a neutral atom has an equal number of protons and electrons, which means the positive and negative charges balance out, resulting in no overall charge.
3. Step 3: Define an ion as an atom or molecule that has gained or lost one or more electrons, causing it to have a net electrical charge (either positive or negative).
4. Step 4: Note that the number of protons in the nucleus does not change when an atom becomes an ion; only the number of electrons changes.
5. Step 5: Conclude that the key difference between a neutral atom and an ion is that a neutral atom has equal numbers of protons and electrons (no net charge), while an ion has an unequal number of electrons and protons, resulting in a net charge.