Ultimate Particle Symbol Weight (Atomic Electrostatic Mass) Electrostatic charge (Units)
       Proton
       Electron
       Neutron
1H1
06-1
0n1
1.007597
0.000548
1.008987
+1
-1
 0 

1 Atomic Mass Unit = 1.66 x 10--24  grams = 931 MeV

or nucleus of the atom. The lower left-hand number is indicative of the numerical magnitude of the positive charge carried by the nucleus and is generally referred to as the "atomic number".

The Beryllium Atom  4Be9

                                    NEUTRON        PROTON       ELECTRON
                               
     Revolving in distant orbits around the atomic nucleus we will find a sufficient number of electrons to confer electrical neutrality on the atom as a whole. For the special case of beryllium we have only four electrons, but the heavier uranium atom, 92U235, has 92 electrons in its orbital shells. The distances between the nucleus of any atom and its orbital electrons are of comparatively vast character when viewed on the atomic scale of magnitudes. A relative analogy between atomic structure and the interstellar configuration of the sun and its planets in outer space is not without value. Like the Universe, the minute atom consists mainly of empty space and its volume is almost devoid of material entities.

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