two or more types of atoms. A molecule is composed of two or more atoms and is the
smallest part of a compound that can exist and still retain the chemical properties of that
compound. Illustrated in Table 1-1 are the relationships of these building blocks and
classifications of matter.
ELEMENT
ELEMENT
COMPOUND
Atoms
Atoms
Molecules
ATOMIC
ATOMIC
ELEMENT
SYMBOL
NUMBER
WEIGHT
Actinium
Ac
89
227
*
Aluminum
Al
13
26.9815
Americium
Am
95
243
Antimony
Sb
51
121.75
Argon
Ar
18
39.948
*
As
33
74.9216
Astatine
At
85
210
*
Barium
Ba
56
137.34
Berkelium
Bk
97
247
Beryllium
Be
4
9.0122
*
Bismuth
Bi
83
208.980
*
Boron
B
5
10.811
*
Bromine
Br
35`
79.909
Cadmium
Cd
48
112.40
*
Calcium
Ca
20
40.08
Californium
Cf
98
249
* Denotes elements most common to medicine.
Table 1-1. Elements, symbols, atomic numbers, and atomic
Weights in alphabetical order (continued).
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