Matching Pairs Periodic Table VocabularyOnline version Use what you learned from your vocabulary flashcards. by Ali Rayfield 1 Bohr model 2 Period 3 Neutron 4 Atomic Mass 5 Group 6 Electron 7 Proton 8 Element 9 Atomic Number 10 Atom The number of protons and the number of electrons found in one atom of an element. A vertical column on the periodic table. It is also known as a family. A substance made of one type of atom found on the periodic table. These substances make up everything in the universe. A subatomic particle located on energy levels that has a negative charge. A basic visual of a single atom with protons, neutrons, and electrons on energy levels. This model was designed by Neils Bohr. The average mass of the protons plus the neutrons in an atom's nucleus. The horizontal rows found on a periodic table. A subatomic particle located in the nucleus with a neutral, or no, charge. The smallest unit a substance can be divided into and still hold the properties of that substance. A subatomic particle located in the nucleus with a positive charge.