8th Chemistry - Electronic Configuration

St. George's College

Subject: 7th CHEMISTRY

Class: Electronic

Teacher's notes

Objectives

Vocabulary

Configuration Date: May 18th

Link and Learn

Prepared by

2009 1

8th Milton A ‐ Electronic Configuration I Name

Oral Intervention

Coin

Chocolate

Sergio María Fernanda Alejandra Almendra Anna Paula Sandra E‐C Maia María Belén Alfredo Kinley Arianne Sandra M. Fiorella Rodrigo Giulia Jaime Stefano Bruno

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8th Milton Alpha ‐ Electronic Configuration I Name

Oral Intervention

Coin

Chocolate

Marcelo Antonella Paulo Alejandro Brenda Diego Gabriel Valeria Cristina Giuliana Joshua María Gracia Gonzalo N. Paolo Gonzalo R. Giorgio Nicolás María Claudia

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Let's remember previous learned concepts...

K ‐ W ‐ L

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ENERGY LEVELS • Electrons move around the nucleus (negative charge around positive charge).

• Even though it looks as if this movement is disorganized, in fact there is a strict organization of the electrons.

• Electrons move around the nucleus packed in Energy Levels.

• Energy levels are the "layers" around the nucleus where electrons are found in motion.

• These energy levels are called Electron shells.

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Rules to fill up the Electron Shells 1. The first electron shell, the closest to the nucleus can hold up to 2 electrons.

2. The other electron shells can hold many more electrons.

3. The last electron shell can only hold up to 8 electrons, this is called the Octet Rule.

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QUANTUM MECHANICS UNCERTAINTY PRINCIPLE ‐ Werner Heisenberg It is not possible to simultaneously determine the speed and position of the electron accurately.

ATOMIC ORBITAL: region in space where it is more probable to find the electron.

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QUANTUM NUMBERS: are mathematical expressions used to describe the energies of atoms, angular moment, electron spin, etc. It is used to determine the distribution of electrons in the atomic orbitals.

Quantum Number

Function

n principal quantum number Energy Level Determines the energy level where the e‐ is located. The higher n value, the farthest the e‐ from the nucleus.

Values 1,2,3,4,5,6,7

Shape of the atomic orbital Energy Sublevel

0 < l < n‐1

m magnetic quantum number Space representation of the It represents the space orientation of atomic orbitals the orbitals in the energy sublevels.

l < m < l‐1

s spin quantum number It describes the spin orientation of the e‐.

‐½, +½

l secondary quantum number (azimuthal or orbital) Determines the energy associated with the e‐ movement around the nucleus; it indicates the energy sublevel.

Shows the electron spin

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Shapes of Atomic Orbitals l secondary quantum number (azimuthal or orbital)

Orbital s: Sphere symmetry.

The size of orbital "s" increases when the principal quantic number increases too.

Orbital p: lobe‐shaped orbitals.

There are 3 types of "p" orbitals, differing by their orientation.

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Orbital d: third sublevel of energy.

There are 5 types of "d" orbitals, with different space orientations.

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Orbital f: complex orientations.

There are 7 types of "f" orbitals, with different space orientations.

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Quantum Numbers n value

1

2

3

4

l value

1

0, 1

0, 1, 2

0, 1, 2, 3

Sublevel value

1

2

3

4

s

p

d

f

l

1

2

3

4

0

3s

0

1

2

1

3p

‐1, 0, 1

3

6

2

3d

‐2, ‐1, 0, 1, 2

5

10

n value

l value

Sublevel

Maximum number of e‐

1

0

s

2(1)2 = 2

2

1

p

2(2)2 = 8

3

2

d

2(3)2 = 18

4

3

f

2(4)2 = 32

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New Knowledge beginning...

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Nucleus Configuration You know the conformation of the nucleus analyzing two pieces of information: 1.

1. Atomic Number: which determines the number of protons.

2.

2. Is the atom an isotope? Which determines the number of neutrons.

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Electron Configuration The Electron Configuration of an atom is the ordered distribution of its electrons in different levels and sublevels of energy.

Pauli's Exclusion Principle In any given atom, there can not be two electron with the same four quantum numbers.

For example, for n = 3, let´s review the quantum numbers: l

1

2

3

4

0

3s

0

1

2

1

3p

‐1, 0, 1

3

6

2

3d

‐2, ‐1, 0, 1, 2

5

10 16

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Progressive Configuration • Electrons are located in a series of levels and sublevels of energy, formed by the atomic orbitals with different size and orientation, holding different but specific number of electrons.

• So, how is that order?

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19

4p 3d

E N E R G Y

4s

3p 3s

2p 2s

1s 20

Electron Configuration of the Elements There are two ways to write the electron configuration of an element: 1. Total Configuration: which considers the writing of all the orbitals.

Example: 2 2 6 2 6 2 10 6 2 10

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Tin: 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p

2. Total Configuration: where it uses the preceding noble gas written in brackets as a starting point.

Example:

Tin: [Kr] 4d105s25p2

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Exercises Determine the Total Electron Configuration of the following elements: • Arsenic • Ir • Thorium • Radon Determine the Partial Electron Configuration of the following elements:

• • • •

Tungsten La Bohrium Lawrencium

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K-W-L Chart What I KNOW about this topic

What I WANT to know about this topic

What I LERANED about this topic

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SURVEY If you want to contribute in improving your Chemistry class, click in the survey link:

Google Forms Term II ‐ 8th Chemistry ‐ Class 1

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Let's check an example on how to fill the electron shells.

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Resources Used Slide (Group)

Description

Resource

Origin

G1 ‐ 2

Image

Beethoven

http://bit.ly/Q7ggk

G1 ‐ 3

Image

Mozart

http://bit.ly/18LkW6

Idea

Notebook Gallery

Electron Shells

http://bit.ly/3Rksdj

G1 ‐ 7 Image

Atomic Orbitals

http://bit.ly/Laor

G1 ‐ 9 Images

Orbital "s" Orbitals "p"

http://bit.ly/3frUSZ http://bit.ly/17brAa

G1 ‐ 10 Image

Orbitals "d"

http://bit.ly/TUPz

G1 ‐ 11 Image

Orbitals "f"

http://bit.ly/GW1Zq

G1 ‐ 13 Image

Electron Shells

http://bit.ly/bJUj

G1 ‐ 15 Animation

Atom

Notebook Gallery

G1 ‐ 17 Image

Atomic Orbitals

http://tinyurl.com/pt2ve3

G1 ‐ 19 Animation

See Saw Rule

Notebook Gallery

G1 ‐ 23 Image

Electron Shells

http://bit.ly/3Rksdj

G1 ‐ 4 Animation

G1 ‐ 6

Image

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Teacher's Notes This class has been designed to cover the topics of Electronic Configuration from Monday May 18th till Friday May 22nd.

For further knowledge about this topic: 1. Conduct a thorough search under the topic: Electronic Configuration of Chemical Elements on the Web, books and magazines.

2. If findings are not specific, ask your teacher for suggestions.

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Objectives • Understand and practice the techniques used to allocate the electrons in the atomic orbitals.

• Use the See‐Saw Rule.

• Use Nemotechniques to remember the electronic configuration of elements.

• Represent any element using the standard electronic configuration.

Note: All, or most, of the objectives will be covered during class time, however the student must be responsible for those objectives not covered or concluded.

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Vocabulary • • • •

Quantum Numbers: Orbitals: Electrons: Octet Rule:

Note: Most of the vocabulary words will be covered during class time, however the student must be responsible for those words not covered or concluded.

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Link and Learn You can visit the following websites to improve your understanding on the present topic: • • • •

http://bit.ly/hLE1o http://science‐learning2009.wikispaces.com http://learningandscience.blogspot.com http://libraryatstgeorge.blogspot.com

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Prepared by

Gerardo LAZARO Science Lead Teacher Email: glazaro@sanjorge.edu.pe Wiki: http://science‐learning.wikispaces.com Blog: http://learningandscience.blogspot.com Twitter: http://twitter.com/glazaro

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Attachments

7th Chemistry ­ Reading 1 ­ Branches of Chemistry ­ Supergoo to the Rescue.docx 7th Chemistry ­ Reading 1 ­ Branches of Chemistry ­ Graphene's Superstrength.docx 7th Chemistry ­ Reading 1 ­ Branches of Chemistry ­ Meteorites may have sparked life on earth.docx 7th Chemistry ­ Reading 1 ­ Branches of Chemistry ­ Plastic munching microbes.docx International System of Units.doc Practical Guide to the International System of Units.pdf Guide for the Use of the International System of Units.pdf