Pick Up:

•Electron Notes•Periodic Table•4 different colored pencils

Electrons are important because they determine how elements will bond and react with other elements.  Electron Configuration – tells us the location of an element’s electrons. Heisenburg Uncertainty Principle – It is impossible to know the exact location and speed of an electron at the same time

Energy Levels – give the general distance from the nucleus Sublevels – the areas within the energy levels where the electrons are found.

s p d f

Electron Configuration

1s1

Energy Level – Principle Quantum #(possibilities are 1-7)

Sublevel(possibilities are

s, p, d, or f)

# of electronss: 1 or 2p: 1-6

d: 1-10f: 1-14

When all written out, Total e- should equal

Atomic #

What element has an electron configuration of 1s1?

1

2

3

4

5

6

7

6

7

d p

f

s

1s

2s

3s

4s

1s

2p

3p

4p

5p

Instructions: Color each section with a different color – be careful with Helium!THEN write the electron configuration in each box for s and p blocks

Aufbau Principle

• Electrons fill the sublevel of lowest energy first.

1s2 2s2 2p6 3s2 3p6 4s2 3d6

Energy

1

2

3

4

5

6

7

6

7

d

f

3d

4d

5d

6d

4f

5f

Subshells d and f are “special”

Instructions: Write the electron configuration in each box for d and f blocks – PAY ATTENTION to what number they start with!

Name the element and circle the sublevel with the highest energy:

_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d6

_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d6

_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p3

Fe

Bi

Os

pd

f

1

2

3

4

5

6

7

6

7

s

Write the electron configuration:

• Br

• Pb

• Er

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p2

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f11

Noble Gas Configuration – shortcut to electron configs based

on the last noble gas.

• Noble gases are found in Group 18.• Example:

[Ar] 4s2 3d8

Where [Ar] represents

Argon – the last noble gas filled

Name the element:

• _____ [Ne] 3s2 3p4

• _____ [Xe] 6s2 4f14 5d6

• _____ [Kr] 5s2 4d10 5p3

S

Os

Sb

Write the noble gas configuration:

• Se

• Mo

• Ar

[Ar] 4s2 3d10 4p4

[Kr] 5s2 4d4

[Ne] 3s2 3p6

Orbital Notation – visually shows the location of the electrons.

• Only 2 electrons fit in each orbital.• Example:

__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ [Xe] 6s2 4f14 5d10 6p5

You must draw each orbital, even if it is empty.• Hund’s Rule – One electron enters each orbital until all orbitals have one electron with parallel spins

• Pauli Exclusion Principle – No 2 electrons can have the same location and same spin

EnergyLevels

Sublevels# of

OrbitalsMaximum

# of electrons

s

p

d

f

1 - 7

2 - 7

3 - 6

4 - 5

2

6

10

14

13

7

5

↑ ↓ ↑ ↑ ↑↑ ↑ ↑ ↑ ↑↑ ↑ ↑ ↑ ↑↑↑↓↓ ↓ ↓ ↓ ↓↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓

Draw the orbital notations for the following elements:

(start with the noble gas config)

• Sn –

• Ba –

• Se –

Lewis Dot Structures – shows the valence electrons.

• Valence Electrons – outershell electrons

• You can count valence electrons by looking at the group #. (if it’s a double digit, subtract 10)

Remember Hund’s Rule when drawing Lewis Dots BUT draw all “s” electrons together on the right.

Examples:

C Br Ba N