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قديم 01-01-2008, 02:13 AM
الصورة الرمزية عاطف خليفة
عاطف خليفة عاطف خليفة غير متواجد حالياً
مدرس الكيمياء للثانوية الازهرية
 
تاريخ التسجيل: Jan 2007
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ATOMIC STRUCTURE

* (1) Rutherford’s Atom:

A)The atomIt is very small, in size it has complicated structure like sun around which electrons ( plants)orbit.

The nucleus
Most of the atomic mass and positive charge are concentrated in the nucleus.

C)The electrons

1- They have negligible mass
2- the sum of electrons (negative charges) equals the number of positive charges (protons).
3- The attraction force of it overcome by another force that equals it in quantity and opposes it in direction namely centrifugal force.

* Objections on Rutherford’s atomic model
It was contradicted by Maxwell’s theory
Maxwell’s theory states that when an electric charged particle moves in an orbit it will lose its energy gradually by radiation and its radius orbit decreases.
By applying this theory on Rutherford’s model, the electrons will lose their energies gradually, their state continuous emission of radiation W consequal gradual decrease in the orbital vadius ,orbits decrease and they spiral inwards until they hit the nucleus.
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