Describe the structure of an atom and the roles... - SS1 Physics Atomic Structure and Radioactivity Question

An atom consists of three main subatomic particles: protons, neutrons, and electrons. Protons have a positive charge and are located in the nucleus at the centre of the atom. Neutrons have no charge and also reside in the nucleus. Electrons have a negative charge and orbit around the nucleus in energy levels or electron shells. Protons and neutrons contribute to the mass of the atom, while electrons are much smaller and have negligible mass.