Do Now

• Describe the 3 rules used to find an element’s electron configuration (hint: Aufbau, Pauli, Hund…)

Do Now

• Describe the 3 rules used to find an element’s electron configuration

• Aufbau Principle – fill up low energy levels first

• Pauli Exclusion Principle – only 2 electrons per orbital

• Hund’s Rule – electrons go to their own orbital before they fill up an occupied orbital

Objective

• I can find the electron configuration of different elements using a mastery quiz

After today, you will be able to…

1. Express the arrangement of electrons through electron configurations in the proper long-form notation

2. Write noble gas notations 3. Identify elements from their

electron configuration

Why Does this Matter?• Writing electron configurations

is like knowing the “address” of an element.

• Knowing the electron configuration can help you locate an element and electrons quickly and efficiently.

• It also tells you which electrons will be involved in chemical bonding.

Homework

• Complete ‘Electron Configuration Part II’ homework on back of guided notes.

• Due Monday/Tuesday

Agenda

• Do Now, Objective (7 min)• Review – Electron configurations

(10 min)• Guided Practice (10 min)• Independent Practice (15 min)• Battleship Practice (15 min)• Mastery Quiz (15 min)

Electron Configurations

• a method of indicating the arrangement of electrons in a particular element or ion.

• You use the total amount of electrons

Electron Configurations

Tell us three things

1.The energy level that the electrons occupy (which you get from the period number)

2.Energy sublevels (s, p, d, f)

3. Number of electrons an atom has

It’s Like Driving!

Rule 1 – Aufbau’s Principle– An electron fills the lowest energy level that it can first

– Just like sitting at a concert

It’s Like Driving!

Rule 2 – Pauli Exclusion Principle– Each orbital can hold a maximum of two electrons

– “Two to a seat”

It’s Like Driving!

Rule 3 – Hund’s Rule– Electrons will fill sublevels of equal energy value one at a time before doubling up

– You would sit by yourself before doubling up

Example: Write the electron configuration for HydrogenHydrogen has 1e-:

1s1

Energy Level (n)

“The street”Sublevel“Neighborhood”

# of electrons“The house”

Hydrogen = “Home”

You try!

• Sulfur

You try!

• Sulfur

1s22s22p63s23p4

You try!

• Zinc

You try!

• Zinc

1s22s22p63s23p64s2 3d10

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

What element is represented by the

electron configuration?

______________________________

Bromine

A New Way to Do it!

Electron Configuration - Carbon

Electron Configuration - Aluminum

Electron Configuration - Germanium

Independent Practice• Complete the five independent

practice problems silently• You have eight minutes• Go!

Independent Practice

• Complete the five independent practice problems silently• Mg – 1s22s22p63s2

• Cr - 1s22s22p63s23p64s2 3d4

• Ar – 1s22s22p63s23p6

• Ca - 1s22s22p63s23p64s2

• Se – 1s22s22p63s23p64s23d104p4

Battleship Practice!• Complete the ‘Battleship’ activity

with a partner• 15 min

Noble Gas Configuration• It is a shortcut to writing electron

configurations• Uses the previous noble gas to

write the electron configuration

Noble Gas Configuration• Steps to writing the noble gas

configuration1. Find the noble gas that comes

right before the element2. Put brackets “[ ]” around the

noble gas’s symbol.3. Continue the electron

configuration normally, after the noble gas.

Guided Practice

• Potassium

Guided Practice

• Chlorine

Guided Practice

• Iodine

Independent Practice• Complete the five independent

practice problems silently• You have eight minutes• Go!

Mastery Quiz

• You have 15 minutes to complete the mastery quiz

• You may use– Periodic table