U3L3 - Lecture Notes - Electron Configurations

Essential Questions

• How are the Pauli exclusion principle, the aufbau principle, and
Hund’s rule used to write electron configurations?

• How do electron-dot structures represent an atom’s valence electrons?

Electron Configuration
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Ground-State Electron Configuration

• The arrangement of electrons in the atom is called the electron configuration.

• The aufbau principle states that each electron occupies the lowest energy
orbital available.

Electron Configuration
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Multiple Choice

The arrangement of electrons in the atom is called the

________ _____________..

• atomic orbital

• electron configuration

• electron arrangement

• primary atomic sequence

Ground-State Electron Configuration

Electron Configuration
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Ground-State Electron
Configuration

• The Pauli exclusion principle states that
a maximum of two electrons can occupy
a single orbital, but only if the electrons
have opposite spins.

• Hund’s rule states that single electrons
with the same spin must occupy each
equal-energy orbital before additional
electrons with opposite spins can
occupy the same energy level orbitals.

Electron Configuration
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Multiple Choice

____'_ rule states that single electrons
with the same spin must occupy each
equal-energy orbital before additional
electrons with opposite spins can
occupy the same energy level orbitals.

• Pauli's

• Rutherford's

• Hund's

• Charles'

Multiple Choice

The Pauli exclusion principle how many electrons can occupy an energy orbital?

• 2

• 4

• 6

• 8

Match

Match the following

• • transition metals

• • actinide series

• • alkali metals

• • noble gases

• d-block

• f-block

• s-block

• p-block

• • d-block

• • f-block

• • s-block

• • p-block

Interactive Table – Electron Configurations and Orbital Diagrams

Electron Configuration
Copyright © McGraw-Hill Education

Go to your ConnectED resources to play Interactive Table: Electron
Configurations and Orbital Diagrams for Elements 1–10.

Interactive Table – Electron Configurations

Electron Configuration
Copyright © McGraw-Hill Education

Go to your ConnectED resources to play Interactive Table: Electron
Configurations for Elements 11–18.

Ground-State Electron Configuration

• The aufbau diagram can be used to write correct ground-state electron
configurations for all elements up to and including Vanadium, atomic number 23.

• The electron configurations for certain transition metals, like chromium and copper, do not follow the aufbau diagram due to increased stability of half-filled and filled sets of s and d orbitals.

Electron Configuration
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Reorder

Reorder these representative elements from fewest valence electrons to most valence electrons.

• Hydrogen (H)

• Boron (B)

• Sulfur (S)

• Bromine (Br)

1

2

3

4

• 1
• 2
• 3
• 4

Valence Electrons

• Valence electrons are defined as
electrons in the atom’s outermost
orbitals—those associated with
the atom’s highest principal
energy level.

• Electron-dot structure consists
of the element’s symbol
representing the nucleus,
surrounded by dots representing
the element’s valence electrons.

Electron Configuration
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Multiple Choice

True or False: Valence electrons are defined as
electrons in the atom’s innermost
orbitals

• True

• False

Multiple Choice

An element's electron configuration and number of valence electrons can be determined by its ______.

• atomic mass

• position on the periodic table

• melting and boiling points

• chemical symbol