| A | B |
|---|
| solid | rigid substance with a definite shape |
| liquid | has a definite volume but takes the shape of its container |
| gas | takes the shape and volume of its container |
| element | contain only one type of atom; cannot be broken down into simpler substances |
| compound | contain two or more kinds of atom |
| molecule | contains atoms bonded together |
| matter | has mass and occupies space |
| chemical property | a substance's ability to change into a different substance |
| physical property | characteristics of a substance that do not involve changing into a different substance |
| physical change | shape, size, or color changes |
| chemical change | transformation into a new substance |
| pure substances | always has the same composition |
| homogeneous | mixture that have the same properties throughout |
| heterogeneous | mixture that has different properties in different parts of the mixture |
| atom | the fundamental unit of which an element is composed |
| electrons | part of the atom with a negative charge and very little mass |
| proton | part of the atom with mass of 1 and charge or 1 |
| nucleus | part of the atom with mass of 1 and charge of 0 |
| Isotopes | atoms with the same number of protons but a different number of neutrons |
| atomic number | number of protons (symbol Z) |
| mass number | number of protons + neutrons (symbol A) |
| group | elements with similar chemical properties existing in columns of the periodic table |
| period | elements within the same row of the periodic table |
| Alkali metals | group1 |
| Alkaline Earth metals | Group 2 |
| Halogens | Group 7 |
| Noble gases | Group 8 |
| Transition metals | In the middle between groups 2 and 3 |
| Metal | tends to lose electrons, solid, shiny |
| Nonmetal | tends to gain electrons, right side of periodic table |
| metalloid | elements that have properties of both metals and non metals |
| diatomic | 2 atoms |
| ion | charges particle that has gained or lost electrons |
| cation | ion with a positive charge |
| anion | ion with a negative charge |
