Loading...

PPT – Electron Configuration PowerPoint presentation | free to download - id: 701d29-MDE2Y

The Adobe Flash plugin is needed to view this content

Electron Configuration

- Mapping the electrons

Electron Configuration

- The way electrons are arranged around the nucleus.

Quantum Mechanical Model

- 1920s
- Werner Heisenberg (Uncertainty Principle)
- Louis de Broglie (electron has wave properties)
- Erwin Schrodinger (mathematical equations using

probability, quantum numbers)

Heisenberg uncertainty principle

- it is impossible to determine simultaneously both

the position and velocity of an electron or any

other particle with any great degree of accuracy

or certainty.

Erwin Schrodinger

- Formulated equation that describes behavior and

energies of subatomic particles. - Incorporates both particle and wave behavior in

terms of wave function - is proportional to the probability of

finding an electron. - Leads to Quantum Mechanics we cannot pinpoint an

electron in an atom but we can define the region

where electrons can be in a particular time

called a Probability map.a 3-dimensional area in

space called an ORBITAL

Principal Quantum Number, n

- Indicates main energy levels
- n 1, 2, 3, 4
- Each main energy level has sub-levels

Energy Sublevels

- s p d f g

- The principle quantum number, n, determines the

number of sublevels within the principle energy

level.

Orbital Quantum Number, l(Angular Momentum

Quantum Number)

- Indicates shape of orbital sublevels
- l n-1
- l sublevel
- 0 s
- 1 p
- 2 d
- 3 f
- 4 g

Orbital

- The space where there is a high probability that

it is occupied by a pair of electrons. - Orbitals are solutions of Schrodingers equations.

Orbitals

Visualizing the orbitals

Orbitals in Sublevels

- Sublevel Orbitals electrons
- s 1 2
- p 3 6
- d 5 10
- f 7 14
- g 9 18

Three rules are used to build the electron

configuration

- Aufbau principle
- Pauli Exclusion Principle
- Hunds Rule

Aufbau Principle

- Electrons occupy orbitals of lower energy first.

Orbital Diagram

Filling Order diagram

-Pauli Exclusion Principle(Wolfgang Pauli,

Austria, 1900-1958)-Electron Spin Quantum Number

- An orbital can hold only two electrons and they

must have opposite spin. - Electron Spin Quantum Number (ms)
- 1/2, -1/2

Hunds Rule

- In a set of orbitals, the electrons will fill the

orbitals in a way that would give the maximum

number of parallel spins (maximum number of

unpaired electrons). - Analogy Students could fill each seat of a

school bus, one person at a time, before doubling

up.

Orbital Diagram for Hydrogen

OrbitalDiagram for Helium

Orbital Diagram for Lithium

Orbital Diagram for Beryllium

Orbital Diagram for Boron

OrbitalDiagram for Carbon

Orbital Diagram for Nitrogen

Orbital Diagram

Notations of Electron Configurations

- Standard
- Shorthand

Orbital Diagram for Fluorine

Standard Notation of Fluorine

Number of electrons in the sub level 2,2,5

1s2 2s2 2p5

Main Energy Level Numbers 1, 2, 2

Sublevels

Shorthand Notation

- Use the last noble gas that is located in the

periodic table right before the element. - Write the symbol of the noble gas in brackets.
- Write the remaining configuration after the

brackets. - Ex Fluorine He 2s2 2p5

Blocks in the Periodic Table