# chapter 5 vocab

Energy levels The fixed energies an electron can have
Quantum The amount of energy required to move an electron from one energy level to another energy level
Quantum mechanical model The modern description, primarily mathematical, of the behavior of electrons in atoms
Atomic orbital a mathematical expression describing the probability of finding an electron at various locations, usually represented by the region of space around the nucleus where there is a high probability of finding an electron
Electron configurations The ways in which electrons are arranged in various orbitals around the nuclei of atoms
Aufbau principle The rule that electrons occupy the S orbitals of lowest-energy first
Pauli Exclusion Principle the contribution each gas in a mixture of gases makes to the total pressure
Spin a quantum mechanical property of electrons and may be thought of as clockwise or counterclockwise
Hund's rule Electrons occupy orbitals of the same energy in a way that makes the number of electrons with the same spin direction as large as possible
Amplitude the wave's height from zero to the crest
Wavelength The distance between the crest
Frequency The number of wave Cycles to pass a given point per unit of time
Hertz the SI unit of cycles per second
Electromagnetic radiation Energy waves that travel in a vacuum at a speed of 2.998 x 10 ^8 m / s; Includes radio waves, microwaves, infrared waves, visible light, ultraviolet waves, X-rays, and gamma rays
Spectrum wavelength of visible light that are separated when a beam of light passes through a prism, range of wavelengths of electromagnetic radiation
Atomic emission spectrum the pattern formed when light passes through a prism or diffraction grating to separate it into the different frequencies of light it contains
Plank's constant the constant (h),which has a value of 6.626 x 10^-34 J * S
Photoelectric effect The ejection of electrons by certain Metals when they absorb light with a frequency table of a threshold frequency
Photons a quantum of light, a discreet bundle of electromagnetic energy that interacts with matter similarily to particles
Ground state The lowest possible energy of an atom described by quantum mechanics
Heisenberg uncertainty principle it is impossible to measure two properties of a quantum object