Atomic structure (negligible electron mass)

Electrons have a relative charge of -1 and roughly a relative atomic mass of 1/1835 (negligible). Protons are found in the atomic nucleus, have a relative electric charge of +1, and a relative mass of 1. Neutrons are found in the atomic nucleus, have no electric charge, and a relative mass of 1. An atom has no electric charge as it contains equal numbers of protons and electrons to balance the charge. The atom has a nucleus surrounded by electrons, with the nuclear radius much smaller than that of the atom.