Unit 1 - Atomic Theory set 2

electromagnetic spectrum

the range of wavelengths or frequencies over which electromagnetic radiation extends.

line spectrum

a spectrum containing radiation of only specific wavelengths

emission spectrum

the spectrum of light released from excited atoms of an element

continuous spectrum

the uninterrupted broad band of all colors (wavelengths) emitted by incandescent solids

Bohr Model

model of the atom in which electrons move rapidly around the nucleus in paths called orbits

Electron Cloud Model

current model of atom in which the electrons seem to form a cloud as they move around the nucleus

wave-particle theory

also known as the duality theory; theory that defines light as a particle (photon) carried on a wave

quanta

The bundle of electromagnetic energy that is absorbed or emitted by matter

excited state

when an atom absorbs energy, its electrons move to a higher energy level

ground state

the lowest possible energy of an atom described by quantum mechanics

quantum theory

describes mathematically the wave properties of electrons and other very small particles

Photon

a particle of light

Wavelength

The distance between two corresponding parts of a wave

Frequency

the number of complete wavelengths that pass a point in a given time

Energy

The ability to do work or cause change

Planck's constant

a number used to calculate the radiant energy (E) absorbed or emitted by a body based on the frequency of radiation

6.626 x 10^-34 J x s

Orbitals/Shells

regions around the nucleus in which given electron or electron pair is likely to be found

Orbits

The path of an electron as it revolves around the nucleus in an atom

quantum numbers

Set of numbers used to completely describe an electron (principal, orbital, magnetic, spin)

shell or energy level

quantized regions of increasing energy (around the nucleus) in which orbitals can be found

subshell (sublevel)

a set of orbitals in an atom that are in the same shell and have the same energy (s, p, d, f)

Aufbau Principle

the rule that electrons occupy the orbitals of lowest energy first

Hund's Rule

states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals

Pauli Exclusion Principle

An atomic orbital may describe at most two electrons, each with opposite spin direction

orbital notation

a diagramic representation that uses dashes and arrows to show the principal energy levels and sublevels for all the electrons in an atom

electron configuration notation

written with numbers/letters (1s2 2s2 2p6...)

Shorthand Electron Configuration Notation

Uses subscripts and noble gases to represent electrons.

Electron Dot/Lewis Structure