111111111111111111

1. 1 2 3 4 5 6 7
H Li Be B C N O
8 9 10 11 12 13 14
F Na Mg Al Si P S
15 16 17
Cl K Ca

3. LAW OF OCTAVES
When elements were arranged in the accenting
order of their atomic masses , each eighth
elements had similar properties as those of the
first

4. Li 7
Na 23
K 39
Ca 40
Sr 87.6
Ba 137.3
Cl 35.5
Br 80
I 127

6. TRIADS
The elements can be classified in groups of
three on the basis of similarities of properties
is known as triads.