Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Understanding Electron Configurations and Orbital Diagrams for Main Group Elements, Study notes of Chemistry

This video provides a step-by-step guide on how to write electron configurations and draw orbital diagrams for main group elements using the periodic table. It covers the order of filling orbitals, the concept of blocks, and the shorthand electron configuration method.

What you will learn

  • What is the difference between a neutral and anion electron configuration for a main group element?
  • How do you draw an orbital diagram for a main group element?
  • How do you write electron configurations for main group elements using the periodic table?

Typology: Study notes

2021/2022

Uploaded on 09/12/2022

anum
anum 🇺🇸

4.6

(8)

243 documents

1 / 2

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Electron Configuration Example Script
This video demonstrates how to write electron configurations and draw orbital diagrams
for main group elements.
To write an electron configuration you could memorize the order in which orbitals are
filled according to their energy level, but a more convenient method is to use the
periodic table. The periodic table is arranged in blocks, each block represents an
orbital, and each space in the block counts as one electron. The s block is the first two
left-hand columns of the periodic table and includes helium. The p block is the last six
columns on the right hand side stating at boron. The d block is the transition metals in
the middle of the periodic table, and the f block is the lanthanide and actinide series.
To begin start at the top left hand corner of the periodic table and work your way down
by reading across a row from left to right and filling in the proper amount of electrons for
each orbital until you reach your element.
Use the number assigned to each row, 1 thru 7, as the value of the principle quantum
number n, when you arrive at the d and f blocks; subtract one from the n value for the
d orbitals, and two from the n value for the f orbitals.
This periodic table has the electron configuration for each row written along the left
hand side using the method just outlined.
Let’s use it to write the electron configuration of a neutral bromine atom, a bromine atom
has 35 electrons.
Using the blocks in the periodic table we can write the electron configuration of bromine
as: 1s22s22p63s23p64s23d104p5.
If we were writing the electron configuration for the bromine anion, we would begin
writing the same configuration as the neutral bromine atom except the number of
electrons in the p orbitals changes from five to six because the bromine ion has 36
electrons.
To write a shorthand electronic configuration use the chemical symbol of the previous
noble gas in square brackets, for bromine it’s argon, then write out the orbitals that are
occupied by valence electrons.
This makes the shorthand electron configuration for bromine [Ar]4s23d104p5.
The last example is an orbital diagram. We are going to draw the orbital diagram for
oxygen. A neutral oxygen atom has 8 electrons, so the orbitals that will contain
electrons are the 1s, 2s and 2p. The levels need to be arranged in order of increasing
energy, and the lowest energy level orbitals are filled first.
pf2

Partial preview of the text

Download Understanding Electron Configurations and Orbital Diagrams for Main Group Elements and more Study notes Chemistry in PDF only on Docsity!

Electron Configuration Example Script

This video demonstrates how to write electron configurations and draw orbital diagrams for main group elements.

To write an electron configuration you could memorize the order in which orbitals are filled according to their energy level, but a more convenient method is to use the periodic table. The periodic table is arranged in blocks, each block represents an orbital, and each space in the block counts as one electron. The s block is the first two left-hand columns of the periodic table and includes helium. The p block is the last six columns on the right hand side stating at boron. The d block is the transition metals in the middle of the periodic table, and the f block is the lanthanide and actinide series.

To begin start at the top left hand corner of the periodic table and work your way down by reading across a row from left to right and filling in the proper amount of electrons for each orbital until you reach your element.

Use the number assigned to each row, 1 thru 7, as the value of the principle quantum number n, when you arrive at the d and f blocks; subtract one from the n value for the d orbitals, and two from the n value for the f orbitals.

This periodic table has the electron configuration for each row written along the left hand side using the method just outlined.

Let’s use it to write the electron configuration of a neutral bromine atom, a bromine atom has 35 electrons.

Using the blocks in the periodic table we can write the electron configuration of bromine as: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5.

If we were writing the electron configuration for the bromine anion, we would begin writing the same configuration as the neutral bromine atom except the number of electrons in the p orbitals changes from five to six because the bromine ion has 36 electrons.

To write a shorthand electronic configuration use the chemical symbol of the previous noble gas in square brackets, for bromine it’s argon, then write out the orbitals that are occupied by valence electrons. This makes the shorthand electron configuration for bromine [Ar]4s^2 3d^10 4p^5.

The last example is an orbital diagram. We are going to draw the orbital diagram for oxygen. A neutral oxygen atom has 8 electrons, so the orbitals that will contain electrons are the 1s, 2s and 2p. The levels need to be arranged in order of increasing energy, and the lowest energy level orbitals are filled first.

Each filled orbital is assigned two electrons of opposite spin according to the Pauli Exclusion Principle. So two of oxygen’s electrons go in the 1s orbital, and two electrons go in the 2s orbital. That leaves four electrons to fill the 2p orbitals.

Remember Hund’s rule and place one electron with the same spin orientation in each of the three p orbitals before pairing the fourth electron.

Now you know the basics of electron configurations and orbital diagrams. You should be able to write electron configurations and draw orbital diagrams for all of the main group elements including ions using this method.