# Notes: More about the Atom ```Construction of
an Atom Notes
Heisenberg Uncertainty Principle
States that we cannot know
the position and the speed of
a moving object
simultaneously

Due to this, we will
discuss where it is
LIKELY that we will find
an electron
Electrons are LAZY!
They will use as little
energy as possible.

Around the Nucleus
Around the nucleus there are
Principal Energy Levels.
The Principal Energy Levels
of Orbitals. The Orbitals
hold the electrons.
Principal Energy Levels

We call them “n”
st
 1 energy level is n=1
nd
2
energy level is n=2
rd
 3 energy level is n=3
th
 4 energy level is n=4
 Etc.
st
1
The energy level has the
lowest of energies and is the
easiest for electrons to live
in (remember, they are
lazy!).
 But if it is full, they have to
nd
go to the 2 energy level
and so on.

Sublevels

The number of sublevels in an
energy level is equal to the
value of n.
st
 1 energy level (n=1) has 1
sublevel (1s)
 2nd energy level (n=2) has 2
sublevels (2s, 2p)
rd
3
energy level (n=3) has 3
sublevels (3s, 3p, 3d)
th
 4 energy level (n=4) has 4
sublevels (4s, 4p, 4d, 4f)
 Notice the names of the
sublevel are a number (same as
n) and a letter (which will have
to do with the orbitals)
Orbitals
All s sublevels (1s, 2s, 3s, etc),
will have 1 orbital
 All p sublevels (2p, 3p, 4p,
etc), will have 3 orbitals
 All d sublevels (3d, 4d, 5d,
etc), will have 5 orbitals
 All f sublevels (4f, 5f, 6f, etc),
will have 7 orbtials

s orbitals are spherically shaped
and there is only 1 type
 p orbitals are dumbbell shaped
and there are 3 types
 d orbitals are complexly shaped
and there are 5 types
 f orbitals are VERY complexly
shaped and there are 7 types

Electrons in the Orbitals
Each orbital can hold a
maximum of 2
electrons
```