| A | B |
|---|
| valence electron | electrons that are farthest away from or most loosely held by the nucleus of an atom and that are involved in chemical reactions |
| electron dot diagram | picture of element surrounded by dots that show the number of valence electrons |
| ion | an atom or group of atoms that has become electrically charged. |
| ionic bond | the attraction between two oppositely charged ions. |
| polyatomic ion | ions made of more than one atom. Many atoms. |
| crystal | an orderly, 3-dimensional arrangement. |
| covalent bond | a chemical bond formed when two atoms share electrons. |
| double bond | a chemical bond formed when atoms share two pairs of electrons. |
| molecular compound | made up of molecules having covalently bonded atoms. |
| polar | a covalent bond in which electrons are shared unequally (NOT equal);a molecule containing polar bonds that do not cancel out. |
| nonpolar | a covalent bond in which electrons are shared equally;a molecule containing NONpolar bonds or polar bonds that cancel out |
| mineral | a naturally occurring solid with a crystal stucture and a definite chemical composition;a simple element that is not organic and that is needed by the body |
| element | A substance that cannot be broken down into any other substances by chemical or physical means/ways. |
| physical change | a characteristic of a substance that can be observed without changing the substance into something else. |
| physical property | a characteristic of a substance that can be observed without changing the substance into something else. |
| chemical property | a characteristic that is observed when a substance interacts with another substance. |
| mixture | 2 or more substances that are missed together in the same place but are not chemically combined are called * |
| molecule | a combination of two or more atoms that are bonded together. |
| group | elements in the same vertical column of the periodic table; also called a family. |
| period | a horizontal->row of elements in the periodic table. |
| alloy | a substance made of two or more elements, (at least 1 is a metal) and has the properties of a metal. |
| metalloids | elements that share the properties of both metals and non-metals. |
