This document provides information about Niels Bohr's model of the atom. It discusses that Bohr's model postulated that electrons revolve around the nucleus in definite circular orbits called energy levels. Electrons can move between these levels by absorbing or emitting energy. The model helped explain atomic spectra but had limitations and could not explain more complex atoms or finer details of spectral lines.

1. PENCHAL REDDY
HIGH SCHOOL
CHEMISTRYCHEMISTRY
Power Point Presentation

3. N. BHARGAV SAI 027
N.SHAKEER 030
P. UMA MAHESH 033
A. MOUNIKA 045

4. About
Neils Henry Bohr
Name: Neil Henry Bohr
Year: 1885 – 1962
Country: Copenhegan (Denmark)
Yearof Noble Prize: 1922

5. Bohr's Model of the Atom
Main Postulates:
 Electronsrevolvearound thenucleusin adefinitecircular path called
orbit or shellsin an atom.
 Theseorbitsor shellscalled Energy Levelsor Energy Shells. Theseare
designated by letters, K,L,M,N.
 TheEnergy of orbitsclosest to nucleushaslowest energy & Farthest
away from thenucleushashighest energy.

6. Bohr's Model of the Atom
 Energy of electron remainsconstant. So, theseshellsarealso called
Stationary States.
 Electronsmovesfrom lower energy level to higher energy level by
absorbing energy.
 Electronsmovesfrom higher energy level to lower energy level by
losing energy.

7. Bohr's Model of the Atom
Nucleus
Electron
Orbit
Energy Levels

8. Bohr's Model of the Atom

9. Bohr's Model of the Atom

10. Bohr's Model of the Atom

11. Bohr's Model of the Atom

12.  Electronsorbit thenucleuslikeplanetsorbit thesun.
 Each orbit can hold aspecific maximum number of
electrons.
Bohr's Model of the Atom

13. Thetheory could not account for thespectraof atomsmorecomplex than
hydrogen.
Thetheory doesnot giveany information regarding thedistribution and
arrangement of electronsin an atom.
It doesn't explain, theexperimentally observed variation in intensity of the
spectral linesof theelement.
Bohr'stheory could not account for thefinestructureof spectral lines.
Bohr'stheory could not explain theStark and Zeeman effects.

14. 1. https://en.wikipedia.org/wiki/Bohr_model
2. http://images.tutorvista.com/cms/images/81/neils-bohr-model-atom1.png
3. https://upload.wikimedia.org/wikipedia/commons/1/17/Bohr_atom_animation_2.gif
5. http://abyss.uoregon.edu/~js/glossary/bohr_atom.html
6. Saraswati Chemistry Text book of 9 CBSE.

15. uerie
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16. Alpha particle
Large angle of deflection, must have hit massive object!
moth
deer
Gold Atom
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