Which statement best explains why the overall charge on an atom is zero?

• A. Atoms contain equal numbers of neutrons and electrons.
• B. The mass of the protons cancels out the mass of the electrons.
• C. The number of protons in the nucleus equals the number of electrons surrounding the nucleus.
• D. Atoms have more electrons than protons, but the charges balance out.

Answer: (C)

Verified step by step guidance

1. Recall that an atom consists of protons, neutrons, and electrons. Protons have a positive charge, electrons have a negative charge, and neutrons are neutral (no charge).
2. Understand that the overall charge of an atom depends on the balance between the number of protons and electrons, since neutrons do not contribute to charge.
3. Recognize that if the number of protons (positive charges) equals the number of electrons (negative charges), their charges cancel each other out, resulting in a net charge of zero.
4. Note that the mass of particles (protons, neutrons, electrons) does not affect the charge balance, so mass considerations are irrelevant to the overall charge.
5. Conclude that the statement 'The number of protons in the nucleus equals the number of electrons surrounding the nucleus' best explains why the overall charge on an atom is zero.