In a neutral atom, the number of electrons equals the number of protons. This is because the positive charge of the protons is balanced by the negative charge of the electrons, resulting in a net charge of zero. However, in ions, which are atoms that have lost or gained electrons, the number of electrons may not be equal to the number of protons. For example, a positively charged ion has lost one or more electrons, so it has more protons than electrons. Conversely, a negatively charged ion has gained one or more electrons, so it has more electrons than protons.