the ways in which electrons are arranged in various orbitals around the nuclei of atoms. need the most stable arrangement possible
electrons occupy the orbitals of lowest energy first.
Pauli exclusion principle
an atomic orbital may describe at most two electrons. to occupy the same orbital electrons must have opposite spins. spins must be paired. one electron enters each orbital until all orbitals contain one electron with the same spin.
each possible electron on Bhor's model has a fixed energy. these are the fixed energies.
of energy is the amount of energy required to move an electron from one energy level to another energy level. "quantized"
quantum mechanical model
the modern description of electrons in atoms. comes from the mathematical solutions to teh schrodinger equation. restricts the energy of electrons to certain values. does not invovle an exact path that an electron takes around the nucleus.
is often thought of as a region of space in which there is a high probability of finding and electron. for each energy level, the Schrodinger equation also leads to a mathematical expression, called an atomic orbital, describing the probability of finding an electron at various locations around the nucleus.
states that 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.
the wave's height from zero to the crest. each complete wave cycle starts at 0.
is the distance between the crests.
represented by a v. the number of wave cycles to pass a given point per unit of time. usually in cycles per second.
the SI unit of cycles per second (Hz). also can be expressed as a recoprocal second (s-1)
light consists of electromagnetic waves. it includes radio waves, microwaves, infrared waves, visible light, ultaviolet waves, X-rays, and gamma rays. they travel at a vacuum.
when sunlight passes through a prism, the different frequencies seperate into spectrum of colors.
atomic emission spectrum
when light passes through a prism the frequencies of light emitted by an element separate into discrete lines to give the atomic emission spectrum of an element.
the lowest possible energy of the electron is its ground state. in the ground state, the electron's principal quantum number (n).
light quantra. the quantra behave as if they were particles. light is described as quantra of energy.
Heisenberg uncertainty principle
states that it is impossible to know exactly both the velocity and the position of a particle at the same time. an aspect of quantum mechanics that is absent in classical mechanics. this limitation is critical in dealing with small particles such as electrons. it does not matter for ordinary sized objects