| Term | Definition |
|---|
| matter | anything that occupies space and has mass |
| element | a pure substance that cannot be broken down into other substances by chemical reactions |
| trace element | an element found in very small amounts, yet essential for good health |
| compound | substance containing two or more elements chemically combined in a fixed ratio |
| atom | the smallest particle of an element that retains the properties of the element |
| proton | subatomic particle having a positive charge; found in nucleus |
| electron | subatomic particle having a negative charge; not in nucleus but surrounds it |
| neutron | subatomic particle without a charge; found in nucleus |
| nucleus | protons and neutrons together; make up the center of an atom |
| atomic number | identifies a specific element; equals the number of protons in an atom of each element |
| radioactive isotope | an unstable atom in which the nucleus decays (breaks down) releasing particles and energy |
| 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 |
| covalent bond | occurs when atoms share electrons |
| molecule | atoms that are held together by covalent bonds |
| chemical reaction | interaction of substances that lead to the formation of new substances |
| reactant | the starting materials for a reaction; found on left side of chemical equation |
| 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 |
| inorganic compound | substance made of two or more elements, none of which is carbon |
| reactive | refers to an atom having energy levels that are not filled, thus it forms bonds |
| inert | refers to an atom having filled energy levels, thus it does not form bonds |
| valence electrons | electrons in the outermost energy level; they are involved in bond formation |
| single bond | a covalent bond in which one pair of electrons is shared |
| double bond | a covalent bond in which four valence electrons are shared between two atoms |
| chemical formula | indicates the number and types of atoms in a molecule |
| structural formula | shows the number and types of atoms in a molecule and how they are arranged |
| space-filled model | is a 3-D representation of a molecule |
| chemical reaction | indicates the formation of new substances from previous substances |
Combine with other sets
Share on Facebook
Share on MySpace