The nucleus of an atom contains which particles?

• A. Protons and neutrons
• B. Electrons
• C. Protons and electrons
• D. Neutrons and electrons

Answer: (A)

The nucleus contains protons and neutrons. Protons carry a positive charge and neutrons have no charge, and together they form the dense center of the atom. Electrons, which are negatively charged, orbit around this nucleus in regions called electron shells or the electron cloud. The nucleus is responsible for most of the atom’s mass, while the arrangement of electrons determines chemical behavior. Because electrons are outside the nucleus, the description that includes electrons in the nucleus isn’t correct. This is why protons and neutrons are the particles found in the nucleus.