l =0 l =1 l =2 l =3
Total number of electrons for
the main energy level
n=1
n=2
n=3
n=4
n=5
n=6
n=7
Increasing
order of
orbital
energy
The principle quantum number (n)
indicates the __________ __________ level
occupied by the electron.
The values of n are positive integers (1,
2, 3, and 4). As n _________________, the
electrons distance from the nucleus and
the electron’s energy _________________.
The Spin quantum number (+ ½ or – ½ )
indicates the orientation of an electrons
magnetic field relative to an outside
magnetic field.
A single orbital can hold a maximum of two
electrons which must have
The Magnetic quantum number (m) is a
subset of the angular momentum
quantum number. It also indicates the
______________ and orientations of the
orbitals around the nucleus. It’s shown
as whole number values (both positive
and negative.
The number of orbitals include:
____ s orbital
____ p orbitals
____ d orbitals
____ f orbitals
__________________ spins.
Principle Quantum
Number
(n)
Magnetic
Quantum Number
(m)
The Angular momentum quantum number
(l) indicates the ___________ or type of
orbital that corresponds to the particular
energy sublevel of that electron. (s, p, d, or
f)
l = _____ is for an ___ orbital
l = _____ is for a ____ orbital
l = _____ is for a ____ orbital
l = _____ is for an ____ orbital
Ex: an electron occupying an orbital with n
= 3 and l = 1 is called a ______ electron
Angular Momentum
Quantum Number
(l)
____ orbitals are spherically symmetrical
around a nucleus, like a hollow ball, made
of chucky material with a nucleus at the
centre.
____ orbitals are like two identical balloons
tied together at the nucleus. These point in
a particular direction (unlike s orbitals).
____orbitals & ____ orbitals have
complicated shapes and orientations.
Spin Quantum
Number
(+ ½ or – ½)
Pauli Exclusion Principle – two particles of
a certain class cannot be in the
________ energy state (cannot have the
same _____ quantum numbers). They can
have the same n, l, and m numbers but the
spin must be ______________________.
_________________ _______________________ - shows the arrangement of
________________ in an atom. Assume arrangements that have the lowest possible
energies.
Aufbau Principle – electrons fill orbitals that have the _________________ energy first.
The structure of each successive element is obtained by adding one proton to the nucleus
of the atom and one electron to the lowest energy orbital that is available.
Electron Configuration Is a Shorthand Notation
Based on the quantum model, the arrangement of the electrons around the nucleus can
be shown by the nucleus’s electron configuration.
Sulfur’s electron configuration.
Atomic Number = 16
Atomic number tells us that sulfur has 16 protons and so 16 electrons.
Practice
1. Write the electron configuration for an atom whose atomic number is 20.
2. Write the electron configuration for an atom that has 17 electrons.
3. What is the atomic number of an element whose atom has the following electron
configuration 1s22s22p63s23p63d24s2
4. Write the electron configuration for an atom that has 13 electrons.