Quantum Wave Model

Electron Configuration

• 4 subshells• S, P, D, F

S Subshell• Spherical in Shape – enables the electrons to

surround the nucleus of the atom• Lowest energy level• 1 orbital (each orbital holds 2 e-)• Holds 2 e-

P Subshell• Dumbbell shaped and can be oriented in

space in one of three ways.• 3 orbitals (each orbital holds 2 e-)• Holds up to 6e-

D Subshell• Dumbbell shaped• 5 orbitals (each orbital holds 2 e-)• Holds 10 e-

F Subshell• Dumbbell shaped• Greatest energy• 7 orbitals (each orbital holds 2 e-)• Holds 14 e-

Orbital Diagrams

• Orbital Diagrams: Electrons enter the electron configuration (orbital diagram) pattern beginning at the lowest energy and filling the pattern to the highest energy.

Hund’s Rule

• Hund’s Rule: Electrons enter the each orbital individually until all orbitals are half filled before pairing with other electrons in the subshell.

• In other words – one electron per orbital until all orbitals are filled, then 2nd electron can be placed in each orbital.

Pauli Exclusion Principle

• Pauli Exclusion Principle: an orbital can contain no more than two electrons and those two electrons must be paired,

• In other words, electrons must have opposite spin (usually indicated by one up-arrow and one down-arrow).

Since there are two spins, the maximum number of electrons in an orbital is 2

Aufbau Principle of Build Up Principle

• Electrons enter orbitals of lowest energy first

• In other words, electrons will enter the subshell 4s2 before subshell 3d10.

Feeling Overwhelmed?

"Teacher, may I be excused? My brain is full."

• Modern Atomic Structure – Brightstorm Link

Let’s Try it.

• Use Mrs. Edie’s chart

__1s__ / __ __ __2s 2p__ / __ __ __ __ __ __ __ __3s 3p 3d__ / __ __ __ __ __ __ __ __ __ __ __ __ __ __ __4s 4p 4d 4f __ / __ __ __ __ __ __ __ __ __ __ __ __ __ __ __5s 5p 5d 5f __ / __ __ __ __ __ __ __ __ __ __ __ __ __ __ __6s 6p 6d 6f

Let’s take a short quiz

Let’s review together

How many energy levels are there?

• 7

The ___ represents?

• The orbital

What is the maximum number of electrons that can be held in one

orbital• 2

How many subshells are in the second energy level?

• 2• 2s and 2p__1s__ / __ __ __2s 2p

How many electrons can occupy in the second energy level?8

How many orbitals are in the f subshell?

• 7__1s__ / __ __ __2s 2p__ / __ __ __ __ __ __ __ __3s 3p 3d__ / __ __ __ __ __ __ __ __ __ __ __ __ __ __ __4s 4p 4d 4f

How many electrons will the third energy level hold?

• 18__1s__ / __ __ __2s 2p__ / __ __ __ __ __ __ __ __ (each orbital will hold 2 electrons)

3s 3p 3d

What four letters represent the subshells?

• S• P• D• F

1s2, 2s2, 2p6,3s23p6

• This is called the _________Configuration• Electron

• What element does this electron configuration represent?

• Argon

The number 2 in 2p6 represents the

• Energy level

The number 6 in 2p6 represents the number of

• Valence Electrons

What is the maximum number of electrons the 4d subshell can hold?

• 10__1s__ / __ __ __2s 2p__ / __ __ __ __ __ __ __ __3s 3p 3d__ / __ __ __ __ __ __ __ __ __ __ __ __ __ __ __4s 4p 4d 4f

What is an easy way to determine the number of valence electrons?

• Look at the periodic table and determine the family the element is in.

Family I – 1 valence electronFamily II – 2 valence electronsFamily III – 3 valence electronsFamily IV – 4 valence electronsFamily V – 5 valence electronsFamily VI – 6 valence electronsFamily VII – 7 valence electronsFamily VIII – 8 valence electrons

Electron Configuration Polka

Song by Michael Offut

There’s a little game that’s as easy as can be,

With numbers and letters and lots of chemistry

It comes from quantum theory and wave mechanics stuff,

But for now just learn the game and that will be enough. 

1-s one, 2-s two, then comes 2-p six,

1-S ONE

2-p six

2-s two

The electron configuration game is really slick,

From alkali to halogen and on to noble gas,

Now you can understand the periodic law at last.

Atoms have orbitals where electrons like to play,

And those electrons fill the orbitals in a special way.

It’s a “building up” process—you can learn it in a second,

And you can call it Aufbau if Deutsch is what you sprechen.

1-s one, 2-s two, then comes 2-p six,

1-S ONE

2-p six

2-s two

The electron configuration game is really slick,

From alkali to halogen and on to noble gas,

Now you can understand the periodic law at last.

The outermost electrons in atoms have to be,

The most important ones for understanding chemistry.

These valence electrons are shared, or lost, or gained,

In chemical reactions when atoms rearrange

1-s one, 2-s two, then comes 2-p six,

1-S ONE

2-p six

2-s two

The electron configuration game is really slick,

From alkali to halogen and on to noble gas,

Now you can understand the periodic law at last.

But the joy is that now. . . at this point in history,

We can finally solve the periodic table mystery.!

Why do elements form families, what is the explanation?

Their valence electrons have the same configuration

1-s one, 2-s two, then comes 2-p six,

1-S ONE

2-p six

2-s two

The electron configuration game is really slick,

From alkali to halogen and on to noble gas,

Now you can understand the periodic law at last.