Electron Configuration

Electron Configuration. Science – 9 Module-1 Week-1.

A. T. O. M. I. C. M. O. D. E. L. S.

Gold. Foil. experiment.

Ernest Rutherford.

Billiard. B al l. Model.

John. Dalton.

Cathode ray tube experiment. Cathode (—) High voltage Anode (+) Cathode ray s Charged plates Battery Magnets Scale on outside of glass.

Sir Joseph John Thomson.

Hydrogen atomic spectra.

Niels Bohr.

Quantum Mechanical Model.

Erwin Schrodinger.

Elements Atomic orbitals Electron Configuration 1s 2s 2p x 2p y 2p z 3s 3p x 3p y 3p z H 1 1p 1 He 2 1s 2 Li 3 1s 2 2s 1 Be 4 1s 2 2s 2 B 5 1s 2 2s 2 2p 1 C 6 1s 2 2s 2 2p 2 N 7 1s 2 2s 2 2p 3 O 8 1s 2 2s 2 2p 4 F 9 1s 2 2s 2 2p 5 Ne 10 1s 2 2s 2 2p 6.

Do you see any pattern in the electron configuration of the elements?.

What are the patterns?. Electron occupy orbital in order of increasing energy..

Electron configuration?. Is the way which electrons arranged in the electron shells of the atom..

Main Energy Levels:. Sublevels and orbitals. The orbits where the electrons revolve around the nucleus are called the main energy levels or shells. These are designated by numbers 1, 2, 3, 4, 5, 6, 7, or letters K, L, M, N, O, P, Q..

The sublevels or subshells:. s. p. d. f. sharp subshell (maximum of 2 electrons).

MAIN ENERGY LEVELS (n) Sublevels (n sublevels) Number of orbitals per sublevel Number of e- per sublevel Number of e- per main energy level (2n) 2 1 (K) 2 (L) 3 (M) 4 (N).

1s 2. Energy Level. Orbital Type. No. of Electron.

Three rules applied in deriving the electron configuration..

2 . PAULI’S EXLUSION PRINCIPLE. Electrons occupying the same orbital must have opposite spin ..

3. HUND’S RULE OF MULTIPLICITY. When an electrons enter a sublevel with more one orbital, they will spread out of the available orbitals with the same spin before pairing..

Write the electron configuration of the elements and show the orbital diagram using Hund’s Rule and Pauli’s Principle..

Thank You….