| A | B |
|---|
| Energy level | The region around the nucleus where an electron is likely to be moving |
| Quantum (of energy) | The amount of energy required to move an electron from its present energy level to the next higher one. |
| The quantum mechanical model | the modern description of the electrons in atoms; derives from the mathematical solution to the Schrodinger equation |
| Atromic orbital | A region in space where there is a high probability of finding an electron. |
| Electron configurations | the ways in which electrons are arranged around the nuclei of atoms |
| The Aufbau principle | Elecrons enter orbital of lowest energy first |
| The Pauli exclusion principle | An atomic orbital amy describe at most two electrons. |
| Hund's rule | When electrons occupy orbitals of equal energy, one electron enters each orbital until all the orbitals contain one electron with spina parallel. |
| Electromagnetic radiation | includes radio waves, microwaves, visible light, infrared and ultraviolent lights, X-rays, and gamma rays. |
| Amplitude | the height of a wave from the origin to the crest |
| Wavelength | the distance between the crests |
| Frequency | the number of wave cycles to pass a given point per unit of time |
| Hertz | in the SI, units of cycles per second |
| Spectrum | when sunlight is passed through a prism the light is separated into a ___ of colors |
| Atomic emission spectrum | Passing the light emitted by an element through a prism gives the ___ of the element. |
| Planck's constant | 6.6262 x 10^-34 J s |
| Photons | Light quanta |
| Photoelectric effect | electrons called photoelectrons are ejected by metals when light shines on them |
| Ground state | the lowest energy level |
| de Broglie's equation | predicts that all matter exhibits wavelike motions |
| Heisenberg uncertainty principle | states that it is impossible to know exactly both the velocity and position og a particle at the same time |
| Periods | the horizonal rows of the periodic table |
| the noble gases | elements in which the outermost s and p are filled |
| the representative elements | elements whose outermost s or p sublevels are only partially filled |
| the transition metals | elements whose outermost s and f have electrons |
| inner transition metals | elements whose outermost s and f contain electrons |
| covalent atomic radius | half of the distance between the nuclei of two atoms in a homonuclear diatomic molecule |
| ionization energy | the energy that is requried to overcome t attraction of the nucelar charge and remove an electron from a gaseous atom |
| electron affinity | the energy change that accompanies the addition of an electron to a gaseous atom |
| electronegativity | the tendency for an atom to attract electrons to itself when it is chemically conbined with another element |
| alkali metals | elements in group 1A |
| alkaline earth metals | elements in group 2A |
| halogens | fluorine, chlorine, bromine, iodine, and astatine |
