Which of these atoms or parts of atoms exhibits no charge?

• A. Proton.
• B. Electron.
• C. Neutron.
• D. Hydrogen nucleus.

Answer: (C)

The thing being tested is which subatomic particle has zero electric charge. Protons carry a positive charge, electrons carry a negative charge, and neutrons have no charge at all. In the nucleus, neutrons add mass but not charge, while protons give the nucleus its positive charge. The hydrogen nucleus is essentially a single proton, so it is positively charged. Therefore, the neutral option is the neutron.