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Quantum Numbers and Atomic Orbital, Electron Configurations and the Periodic Table
is a positive integer representing the principle quantum number
is an integer representing the angular momentum
is an integer from-l through 0 to +l, called the magnetic quantum number, prescribing the 3D orientation of the orbital of in the space around the nucleus.
indicates the spin of the electron and is only +1/2 or -1/2.
The square of the wave function gives the
probability of electron density
a measure of the probability of finding an electron of a particular energy in a particular region of the atom.
An atomic orbital is specified by
three quantum numbers. they are: principle quantum number (n), angular momentum (l), magnetic quantum number (m_l).
Indicates the relative size of the orbital (and therefore the relative distance from the nucleus)
an integer from 0 to (n-1)
indicates the shape of the orbital
a positive integer
Indicates the relative size of the orbital and relative distance from the nucleus
an integer from 0 to (n-1)
an integer with values from -l to +l
Indicates the spatial orientation of the orbital
energy levels (shells) , given by n value
the smaller the n value the lower the ...
energy level and the greater the probability the electron is closer to the nucleus
levels are divided into these, given by the l value
l = 0 is an (what subshell)
l = 2 is a (what subshell)
l = 1 is a (what subshell)
l = 3 is an (what subshell)
described by each combination of n, l, and ml, specifies the size (energy), shape, and spatial orientation of one of the atom's orbitals
energy of the atom
mathematical description of the electrons wavelike behavior in an atom.
S orbitals are
p orbitals are
d orbitals are
Each electron in any atom is described completely by a set of
4 quantum numbers: n,l,m_l, and m_s
The first three quantum numbers of an electron n, l, and m_l describe the
The fourth quantum number describes the
Pauli's exclusion principle
No two electrons in the same atom can have the same four quantum numbers
An atomic orbital
what can hold a maximum of two electrons, with a must have opposing spins.
The energies of atomic orbitals are affected by
nuclear charge (Z), and shielding by other electrons
A higher nuclear charge increases
nucleus-electron interactions and lowers sublevel energy
Shielding by other electrons reduces
the full nuclear charge to an effective nuclear charge (Zeff)
is the nuclear charge an electron actually experiences
Orbital shape affects
attraction of opposite charges and repulsion of like charges
Energy states of many-electron systems are affected by ________ which gives rise to ______.
electron-electron repulsions/the splitting of energy levels into sublevels
Electrons in the same energy level shield
each other to an extent
Electrons in inner energy levels shield
the outer electrons very effectively.
The further from the nucleus an electron is, the lower the
Zeff for that particular electron. (effective nuclear charge)
Penetration increases ______ and decreases _______
Orbital shape causes electrons in some orbitals to ____________ close to the nucleus.
Orbital shape causes electrons in some orbitals to "penetrate" close to the nucleus.
Each energy level is split into _______ of differing __________
Splitting is caused by _____ and its effect on
, a lower l value indicates
a lower energy sublevel.
The aufbau principle
electrons are always placed in the lowest energy sublevel available
specifies that when orbitals of equal energy are available, the lowest energy electron configuration has the maximum number of unpaired electrons with parallel spins
Elements in the same group of the periodic table have the same
outer electron configuration
Elements in the same group of the periodic table exhibit similar
Similar outer electron configurations correlate with similar
Inner (core) electrons are those an atom has in common with
the pervious noble gas and any completed transition series
Outer electrons are those in the _______ energy level.
Valence electrons are those involved in forming
For main group elements, the valence electrons are the
For transition elements, the valence electrons include the outer electrons and
any (n-1)d electrons