| A | B |
|---|
| atom | the smallest particle of an element that has the properties of the element and can exist either alone or in combination |
| atomic structure | number & arrangement of protons, neutrons, & electrons in an atom |
| chemical change | when substances combine to form a new substance |
| chemical equation | model of chemical changes illustrating how elements become rearranged in a chemical reaction |
| chemical formula | shorthand way to represent compounds |
| chemical properties | characteristic of a substance that can only be observed during a reaction |
| chemical reaction | a change in which one or more substances are converted into different substances |
| chemical symbol | a shorthand way to write the name of an element |
| compound | substance made of the combined atoms of two or more elements |
| electron | negatively charged particle that move around the nucleus of an atom |
| element | substance in which all the atoms in a sample are alike |
| matter | the substance of the universe: something that occupies space and has mass |
| neutron | atomic particle with no charge (neutral) that is part of an atom’s nucleus |
| nucleus | the positively charged center of an atom that contains protons and neutrons |
| physical change | a change that does not change the chemical composition of a substance |
| physical properties | characteristic that can be observed or measured without changing the composition of matter. |
| proton | atomic particle with a positive charge that is part of an atom’s nucleus |
| subatomic | a particle smaller than an atom |
| subscript | the number of atoms for a particular element represented by a small number to the right of the element’s symbol |
