distribution of electrons in various shells

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Distribution of electrons in various shells. Learning Objective:

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Learning Objective:. Distribution of electrons in various shells. How are Electrons Distributed in Different Orbits (Shells)?. The distribution of electrons into different orbits of an atom was suggested by Bohr and Bury. - PowerPoint PPT Presentation

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Page 1: Distribution  of electrons in various shells

Distribution of electrons in various shells.

Learning Objective:

Page 2: Distribution  of electrons in various shells

How are Electrons Distributed in Different Orbits (Shells)?The distribution of electrons into different orbits of an atom was suggested by Bohr and Bury.

The energy of the K shell is the least while those of L, M, N and O shells increases progressively. We also know that any system that has least energy is the most stable.1st energy level is K shell 2nd energy level is L shell 3rd energy level is M shell 4th energy level is N shell and so on

Page 3: Distribution  of electrons in various shells

Bohr and Bury Scheme - Important Rules

Maximum number of electrons that can be accommodated in a shell is given by 2n2 where n = shell number

For 1st energy level, n = 1Maximum number of electrons in 1st energy level = 2n22 x (1) 2 = 2

For 2nd energy level n = 2Maximum number of electrons in the 2nd energy level = 2n22 x 22 = 2 x 4 = 8

For 3rd energy level n = 3Maximum number of electrons in the 3rd energy level = 2n2= 2x(3) 2= 2 x 9 = 18

For 4th energy level n = 4 Maximum number of electrons in the 4th energy level = 2n2= 2x(4) 2= 2x16 = 32

Page 4: Distribution  of electrons in various shells

Sl.No Electron Shell Maximum Capacity

1 K Shell 2 electrons

2 L Shell 8 electrons

3 M shell 18 electrons

4 N shell 32 electrons

Bohr and Bury Scheme - Important Rules

Page 5: Distribution  of electrons in various shells

Electronic Configurations of Some Important Elements

Page 6: Distribution  of electrons in various shells

Geometric Representation of Atomic Structure

Below are the examples on Geometric Representation of Atomic StructureExample: 1

 24 Mg12

Steps: 

•The first 2 electrons will go to the 1st shell = K Shell (2n2)•The next shell L takes a maximum of 8 electrons (2n2)•In this way 2 + 8 = 10 electrons have been accommodated. The next 2 electrons go to the M Shell.

Page 7: Distribution  of electrons in various shells

Atomic structures of the First Twenty Elements

Page 8: Distribution  of electrons in various shells