This document summarizes key information about subatomic particles including protons, neutrons, electrons, isotopes, and ions. Protons have a positive charge and are found in the nucleus. Neutrons have no charge and are also found in the nucleus. Electrons have a negative charge and are found outside the nucleus. The number of protons determines the element. The number of neutrons can vary between isotopes of the same element. Isotopes are identified using hyphen or nuclear notation. To find the number of neutrons in an isotope, subtract the atomic number from the atomic mass. The number of electrons in a neutral atom equals the number of protons. Ions have a different number of electrons than

1. Subatomic Particles Names, Properties, and Locations Atomic mass and isotopic mass Ions by Lisa Allen

8. Electrons Negative Charge Found in energy levels outside the nucleus Mass of 1/1836 AMU (almost nothing!) The number of electrons in a neutral atom is equal to the number of protons. The number of electrons in an ion is different from the number of protons .