| A | B |
|---|
| Law of conservation of mass | In all changes, mass is exactly conserved, provided nothing is added and nothing escapes. must be in a closed system |
| Laws of society | legislated; that is, they are agreed upon and then enforced. can be changed or repealed. if you violate this law you are punished |
| Law of Nature | is not changed or repealed often. if one violates this law he is not punished. |
| electronic balance | with this balance, it takes only seconds to mass an object; can not put more than 100g on this. |
| single- pan balance | must be "zeroed" on a level surface before each use. |
| equal- arm balance | simplest balance |
| gram | the fundamental unit of mass in the metric system |
| characteristic properties | properties that show differences between substances |
| Freezing point | point when substance changes from liquid to hard solid; the plateau or flat section |
| melting point | same temperature as freezing point |
