All terms in this list:

valence electrons: electrons in the outermost energy level; they are involved in bond formation

structural formula: shows the number and types of atoms in a molecule and how they are arranged

single bond: a covalent bond in which one pair of electrons is shared

reactant: the starting materials for a reaction; found on left side of chemical equation

radioactive isotope: an unstable atom in which the nucleus decays (breaks down) releasing particles and energy

proton: subatomic particle having a positive charge; found in nucleus

product: ending materials of a reaction; found on right side of chemical equation

organic compound: substance made of two or more elements, one being carbon

nucleus: protons and neutrons together; make up the center of an atom

neutron: subatomic particle without a charge; found in nucleus

molecule: atoms that are held together by covalent bonds

matter: anything that occupies space and has mass

isotope: atoms having the same numbers of protons but different numbers of neutrons

ionic bond: occurs when atoms transfer electrons to other atoms

ion: atoms that have lost or gained electrons

inorganic compound: substance made of two or more elements, none of which is carbon

element: a pure substance that cannot be broken down into other substances by chemical reactions

electron: subatomic particle having a negative charge; not in nucleus but surrounds it

double bond: a covalent bond in which four valence electrons are shared between two atoms

covalent bond: occurs when atoms share electrons

compound: substance containing two or more elements chemically combined in a fixed ratio

chemical reaction: interaction of substances that lead to the formation of new substances

chemical reaction: indicates the formation of new substances from previous substances

chemical formula: indicates the number and types of atoms in a molecule

atomic number: identifies a specific element; equals the number of protons in an atom of each element

atom: the smallest particle of an element that retains the properties of the element