Worksheet: Electron Distributions Name___________________
CHEMISTRY: A Study of Matter
© 2004, GPB
3.19a
KEY
1. There are four types of orbitals:
s : shaped like a ___________
An E level can contain only _____ s orbital, making up the “s sublevel”.
p : shaped like ____________
An E level can contain _____ p orbitals, making up the “p sublevel”.
d : shaped like double dumbbells
An E level can contain _____ d orbitals, making up the “d sublevel”.
f : too complex to draw or describe
An E level can contain _____ f orbitals, making up the “f sublevel”.
2. Each orbital can hold a maximum of _____ electrons. Since both electrons
have a __________ charge, they __________. What keeps them from
flying apart?
Each electron _______ on its axis. One spins __________
and the other spins _____________. When charged particles spin,
they act like tiny magnets. Since the two electrons spin
in ___________ directions, one acts like the north pole of a magnet
and the other acts like the south pole. This makes the electrons
_____________ .
3. Since each orbital can hold _____ electrons:
The “s sublevel” can hold ______ electrons.
The “p” sublevel can hold ______ electrons.
The “d” sublevel can hold ______ electrons.
The “f” sublevel can hold ______ electrons.
We use this notation to describe an electron:
main _______ level 3p
5
# of e- in __________
__________
How are electrons distributed within a sublevel?
According to Hund’s Rule, each __________ within a sublevel is
half-filled before any is __________.
sphere
dumbbells
1
3
5
7
2
negative
repel
spins
clockwise
counter-clockwise
opposite
attract
2
2
6
10
14
energy
sublevel
sublevel
orbital
filled
CHEMISTRY: A Study of Matter
© 2004, GPB
3.19b
We draw orbital diagrams to show the distribution of electrons in a sublevel.
Circles are used to represent the individual ________. __________ are used to
represent electrons in the orbital. The first electron in an orbital is represented
by a
!
and the second by a
!
.
A set of four ______________ numbers is assigned to each __________ to
describe its energy and location within the atom. The quantum numbers use the
symbols _______, _______, _______, and _______.
_______ is the principle quantum number and represents the ________ level of
the electron.
_______ represents the sublevel of the electron, which depends on the type of
_____________.
Pauli’s Exclusion Principle states that within an atom, no two electrons can have
the same set of _____________ _____________. If two electrons have the
same n, l, and m numbers, they are in the same _______ level, the same
___________, and the same _____________. They must then have
____________spins! So, the s quantum numbers must be different.
Practice: Write electron distributions and do the orbital notation for the
following:
1. P :
2. Ca:
Only do the electron distributions for the following:
1. Co:
2. Eu:
3. Tc:
orbitals
Arrows
quantum
electron
n l m s
n
energy
l
orbital
quantum numbers
energy
sublevel
orbital
different/opposite
!"
!
1s
2
2s
2
2p
6
3s
2
3p
3
1s 2s 2p 3s 3p
!"
!"
!"
!"
!"
!
!
1s
2
2s
2
2p
6
3s
2
3p
6
4s
2
1s 2s 2p 3s 3p 4s
!"
!"
!"
!"
!"
!"
!"
!"
!"
!"
1s
2
2s
2
2p
6
3s
2
3p
6
4s
2
3d
7
1s
2
2s
2
2p
6
3s
2
3p
6
4s
2
3d
10
4p
6
5s
2
4d
10
5p
6
6s
2
4f
7
1s
2
2s
2
2p
6
3s
2
3p
6
4s
2
3d
10
4p
6
5s
2
4d
5
