| A | B |
|---|
| atom | building block of matter; contains neutrons, protons and electrons |
| subatomic particle | protons, neutrons and electrons |
| proton | positively charged particle in atoms nucleus |
| electron | negatively charged particle that occupies space atound the nucleus |
| neutron | particle without a charge in nucleus |
| element | pure substance composed of only one type of atoms; cant be broken down into another substance |
| isotope | atom with different # of neutrons |
| ion | atom with different # of electrons |
| compound | two or more different elements combined |
| covalent bond | type of chemical bond formed when atoms share electrons |
| ionic bond | electrical attraction between two oppositely charged atoms or groups of atoms |
| chemical reaction | energy requiring process by which atoms in substances are changed into different substances |
| reactants | substance that exists before a chemical reaction starts. Located on the left side of the arrow in a chemical equation. |
| products | substance formed by a chemical reaction; located on the right side of the arrow in a chemical equation |
| activation energy | minimum amounts of energy needed for reactants to form products in a chemical reaction. |
| catalyst | substance that speeds up a chemical reaction by reducing the activation level |
| enzymes | protein that speeds up a biological reaction by lowering the activation energy needed to start the reaction |
| active site | specific place where a substance binds on an enzyme |
| acids | less than ph7 |
| bases | Ph is greater than 7 |
| buffer | mixture that can react with an acid or a base to maintain the ph within a specific range. |
| endothermic | heat energy goes into a system |
| exothermic | heat energy exits a system |
