Chapter 4 Flashcards
electromagnetic radiation
a form of energy that exhibits wave light behavior as it travels through space
electromagnetic spectrum
all forms of electromagnetic radiation
wavelength
the distance between corresponding points on adjacent waves.
Frequency
the number of waves that pass a given point in a specific time, usually one second.
photoelectric effect
refers to the emission of electrons from a metal when light shines on the metal.
Quuantum
the minimum quantity of energy that can be lost or gained by an atom.
photon
a particle of electromagnetic radiation having zero mass and carrying a quantum of energy.
Ground State
lowest energy state of an atom.
excited state
when a atom has a higher potential energy than its ground state
line-emission spetrum
specific frequencies emitted by the element.
continuous spectrum
emission of a continuous range of frequencies of electromagnetic radiation
Heisenberg uncertainty principle
it is impossible to determine simultaneously both the position and velocity of an electron or any other particle
Quantum theory
describes mathematically the wave properties of electrons and other very small particles.
orbital
a three dimensional region around the nucleus that indicates the probable location of an electron.
Quantum numbers
specify the properties of atomic orbitals and the properties of electrons in orbitals
Principal quantum numbers
symbolized by “n” indicates the main energy level occupied by the electron
Angular momentum quantum number
symbolized by ‘l’ indicates the shape of an orbital
manetic quantum number
symbolized by ‘m’indicates the orientation of an orbital around the nucleus.
Spin quantum number
only 2 possible values (+1/2, -1/2) indicates the 2 fundamental spin states of an electron in an orbital.
electron configuration
the arrangement of electrons in an atom
aufbau principle
an electron occupies the lowest energy orbital that can receive it.
Pauli extension principle
no two electrons in the same atom can have the same set of four quantum numbers.
Hund’s rule
orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron
highest occupied level
the electron containing main energy level with the highest principal quantum number.
