| A | B |
|---|
| atomic mass | average mass of 1 atom |
| periodic table | orderly arrangement of elements acc. to atomic mass |
| nucleus | core of atom |
| proton | positively charged particles in nucleus |
| neutron | particles w/out charge found in nucleus |
| electron | negatively charged particle located outside of nucleus |
| atomic mass unit | measurement of particles in an atom |
| atomic number | number of protons in nucleus |
| chemical symbol | 2 letters representing the element on periodic chart |
| group | column or family |
| family | column or group |
| period | row |
| valence electron | electron involved in sharing or transfer |
| malleable | can be hammered or molded into different shape |
| ductile | can be stretched into wire |
| conductor | easily transfers heat or electricity |
| magnetic | can be made into magnet or attracts them |
| reactivity | ease and speed with which an element combines or reacts with other element or compound |
| corrosion | process of reaction and wearing away |
| alloy | mixture of metals |
| alkali metal | most reactive of all metals, always combined in nature |
| alkaline earth metal | not as reactive as alkali metals, bright, hard, good conductor |
| transition metal | metals which are a bridge between very reactive ones and less reactive ones |
| lanthanide | rare earth metal which is soft, malleable, shiny, and very conducive for electricity |
| actinide | rare earth metal |
