Radiation Safety Practice Exam

Which subatomic particle has a positive charge?

1. Neutron

2. Proton

3. Electron

4. Photon

The correct answer is: Proton

The subatomic particle that carries a positive charge is the proton. Protons are found in the nucleus of an atom and are one of the primary building blocks that define the atomic number of an element, which in turn determines its chemical properties. Their positive charge contributes to the overall charge balance within an atom, where they attract negatively charged electrons, allowing for the formation of stable atomic structures. In contrast, neutrons are neutral particles, meaning they have no electrical charge and also reside in the nucleus. Electrons carry a negative charge and orbit around the nucleus in various energy levels. Photons are not particles that reside within atoms but rather are particles of light, characterized by having no mass and no charge. In the context of atomic structure and charge, the proton is fundamental for understanding how atoms interact with one another and the role they play in chemical reactions.