All matter is made up of tiny particles called . Atoms are made up of three subatomic particles known as , , and . Protons and neutrons are located in the . The nucleus is dense and takes up very little space within the atom. All protons have a charge (p+) and have a mass of about 1 amu. All neutrons have no charge or are (no) and have a mass of about 1 amu.
Electrons are located in the area known as the electron cloud. Electrons orbit around the nucleus and have a charge (e-).