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Microcosmology: Atom
There exist in nature 92 different chemical elements i.e. 92 different kinds of atoms. While some of these elements such as oxygen, nitrogen, carbon, etc., are rather abundant, some others such as lanthanum, cerium, etc. are very rare. In addition to 92 natural elements, modern science has succeeded in making several entirely new elements artificially. Combining among themselves in various proportions, the atoms of these basic elements form the unlimited number of various substances, some simple and common such as water; others complex chemical materials such as sugar, starch, cellulose.
1. The following elements have been artificially made by man: Atomic No.
Symbol
Name NEPTUNIUM
93
94
PLUTONIUM
95
AMERICIUM
96
CURIUM
BERKELIUM
CALIFORNIUM
EINSTEINIUM
FERMIUM
97
98
99
100
101
102
103
MENDELEYIUM
NOBELIUM
LAWRENCIUM
£ § 2
Np
Pu
Am
Cm
Bk
Cf
Ei
Fm
Md
No
Lw
