Earl's Atomic Theories

Rutherford's Atom:
Rutherford did his Gold Foil experiment from which he concluded that an atoms nucleus is of a positive charge. He also said it is densely packed into the center of an atom. Through he experiment, he also concluded that the atom was mostly space. With small electrons floating freely in it. He thought of the atom as being like a plum pie. The nucleus is in the middle while the electrons, like plums, where placed throughout the pie (see picture).
 

The Bohr Model of the Atom:
Bohr is the father of the modern atomic theory. He expanded on Rutherford's atom. He thought of a way to explain why each atom had discrete atomic emmisions (light given off when excited). He said the electrons are in orbits. These orbits are quantized, or in other words they are multiples of some value. He said an electron can never be in-between any two levels, but must exist in one or the other. This is the basis of modern atomic theory.

The Electron Levels:
In theorizing how the atom looked, Bohr also had to decide where the electrons lied. He called these quantized levels orbitals. For each energy level, after the first two, there are four types of orbitals. The S, P, D, and F. The first energy level only has the S-orbital, and the second energy level has both S and P orbitals. The S orbital holds two electrons, while the P holds 6, and the D holds 10. Electrons are not put into the P orbital until the S orbital is full. Then when the P is full the electrons start on the D.  The F orbital begins to hold electrons when the S, P, and D orbitals are full.  This is how the Periodic Table is arranged.

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