| A | B |
|---|
| Chemical potential energy | battery |
| law of conservation of energy | energy is neither created nor destroyed |
| physical property | something that can be observed without altering its identity |
| chemical property | something that cannot be observed without altering its identity |
| physical change | process by which a substance undergoes change that does not alter its identity |
| chemical change | to alter the identity of a substance |
| atomic number | number of protons in the nucleus of an atom |
| constant | stays the same |
| natural law | describes how nature behaves but does not describe why things happen |
| hypothesis | proposed, but unproved, explanation of observed facts |
| isotope | atom that has the same number of protons as another atom, but that has a different number of neutrons |
