Orbital Notation and Lewis Dot Structure
Note Taking Guide

Electron Configuration Rules:

  1. ______

Each electron MUST occupy the lowest energy orbital available first

  1. ______

A maximum of 2 electrons can occupy a single orbital, but only if the electrons have opposite spins

  1. ______

Single electrons with the same spin must occupy each equal energy orbital before additional electrons with opposite spins can occupy those same orbitals

Aufbau’s Principle:

Each electron MUST occupy the ______energy level and sublevel available first.

Determine the order of energy levels, sub-levels, and the orbitals within the sub-levels

Energy levels are in the order of the periods down the periodic table

Order: ______

Sub-levels: are in the order of ______

Remember that ____ and _____ sublevels are behind the s and p sublevels.

Pauli Exclusion Principle:

A maximum of ____ electrons can occupy a single orbital, but only if the electrons have ______spins.

Remember the amount of orbitals in each sub-level

S-sublevel = 1 orbital = _____ electrons

P-sublevel = 3 orbitals = _____ electrons

D-sublevel = 5 orbitals = _____ electrons

F=sublevel = 7 orbitals = _____ electrons

Each energy level holds a set amount of electrons:

1st energy level = ___sublevel and ____ orbital = max 2 electrons

2nd & 7th energy level = 2 sublevels and 4 orbitals = max _____ electrons

3rd & 6th energy level = 3 sublevels and 9 orbitals = max _____ electrons

4th – 5th energy levels = 4 sublevels and 16 orbitals = max ____ electrons

Hund’s Rule:

Single electrons with the same spin must occupy each equal energy orbital before additional electrons with opposite spins can occupy those same orbitals.

Orbital Notation:

Shows the electrons in an orbital and their ______

S- ___ orbital, p- ____ orbitals, d – ____ orbitals, and f –____ orbitals

Lines represent the ______

The number of the energy level and its sublevel are written below the line

Uses up and down arrows to represent the electrons and their spins

Example: Lithium – 1s22s1

______

1s 2s

Let’s Try Nitrogen:1s22s22p3

______

1s 2s 2p

*This is called an orbital diagram/notation

Practice:

What is Sulfur’s electron configuration?

______

What is Sulfur’s orbital notation?

Write the orbital diagrams for the following elements:

Manganese

Potassium

Gallium

*Remember: S- 1 orbital, p- 3 orbitals, d – 5orbitals, and f – 7 orbitals

Valence Electrons:

The electrons that determine the ______properties of an element

The electrons in the highest (outermost) ______

How do we know what is the highest/outermost energy level?

The electron configuration for Chlorine is:

1s2 2s2 2p63s2 3p5

•The outermost energy level is the 3rd energy level

•Chlorine has 7 valence electrons (2 + 5 = 7)

Complete the table:

Element / Electron Configuration / # of Valence Electrons
Sodium
Carbon
Gallium
Oxygen
Fluorine

How to use the periodic table to determine the number of valence electrons:

Lewis Dot Structure:

A model that uses electron-dot structures to show how electrons are arranged in molecules.

Shows the valence electrons around the ______

What is an element symbol?

Aluminum = ______

Aluminum has _____ valence electrons

Imagine aluminum symbol with a box around it:

*Each side of the box can only hold ____ electrons

*Put 1 dot (to represent 1 electron) on each side before adding a second dot to that side of the box – ______

So the final product looks like this: Al

Give Sulfur a Try:

How many valence electrons does sulfur have? ____

Draw sulfur’s Lewis dot structure:

S

Complete the table:

Element / Symbol / # of valence electrons / Lewis Dot Structure:
Lithium
Nitrogen
Calcium
Bromine
Carbon
Selenium