click below
click below
Normal Size Small Size show me how
Phy. S. Chap. 17&18
| Term | Definition |
|---|---|
| Element | Any pure substance that is made of only one kind of atom. |
| 4 elements | Air, Fire, Earth, Water |
| There are _______ amount of elements | 117 |
| There are _______ amount of natural occurring elements | 92 |
| The 11 gases | H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn |
| Monotomic elements | have 1 atom in natural state |
| Noble gases | He, Ne, Ar, Kr, Xe, Rn |
| Diatomic elements | H2, N2, O2, F2, Cl2, Br2, I2 |
| Dmitri Mendeleev | arranged the elements into what eventually became the periodic table today |
| Johann Dobereiner | placed the elements in order of increasing mass. (he called them triads. |
| Periodicity | repetition of certain properties at regular intervals when elements were placed in order of atomic mass |
| Henry Moseley | discovered how to use x-rays. He lead the revision of the periodic table. |
| Metals | belong to families with few valence electrons |
| Non-metals | hold their electrons tightly, so their properties are very different from metals |
| the horizontal rows of the periodic table are called | periods or series |
| The period number tells | how many main energy levels the elements in that period have in their ground state |
| ground state | lowest energy state for electrons |
| The more energy levels | the larger it is |
| Cations | positive and have more protons |
| Anion | negative and has less protons |
| Electron affinity | deals with the strength of attraction of electrons to unbonded atoms |
| electroegativity | deals with an atoms ability to attract and hold electrons when bonded to other atoms |
| Covalent bonds | nonmetal /nonmetal; sharing |
| ionic bonds | metal/ nonmetal ; giving away and taking electrons |
| metallic bonds | metal/metal ; everyone sharing |