Line spectrum of sun rays shows that composed of hydrogen and Helium.
The principles of Modern Atomic Theory:
1 – Dual nature of electron.
2 – The Heisenberg uncertainty principle.
3 – Finding the mathematical expression which describes the wave motion of electron, its shape and its energy.
1 – The dual nature of the electron
The experimental data showed that the electron has a dual nature i.e
a) It is a material particle. b) It has wave properties.
* De Broglie principle:
Every moving body (such as electron or the nucleus of an atom or whole molecule)is associated with (accompanied by) a wave motion (or matter waves) which has some properties of light waves.
The matter wave motion differs from electromagnetic waves n …………
1- They are not separating from the moving body
1- They are separated from the moving body
2- Their speed is not equal to the speed of light
Their speed is equal to the speed of light
2- The Heisenberg uncertainty principle: (quantum mechanics)
It is practically impossible to determine both position and the velocity of the electron exactly (precisely) at the same time. We can only say that it is probably to a greater r lesser extent to locate the electron in this or in that place. This is to speak in terms of probability seems to be more precise.
3. The wave equation for motion of electron inside the atom:
(Schrodinger wave mechanics theory): He applied the ideas of Blanck, Einestein, De Broglie and Heisenberg so he shows that:
v It is possible to determine the allowed energy levels of the electron and define the region of space around the nucleus where it is most probable to find the electron in each energy level.