Page 13 - classification of elements

Helium is always in duplet state.

All other elements of group 18

of modern periodic table are

always in octet state.

All other elements try to be in either

octet state or in duplet state by either loosing or taking

electrons or by sharing electrons.[Periodic Table]

No. of Electronic Valence shell No. of Valency Remarks

electrons configuration valence

electrons

He 2 1s 2 1s 2 2 0 Duplet

2
2
2
Ne 10 1s 2s 2p 6 2s 2p 6 8 0 Octet

2
2
2
2
6
Ar 18 1s 2s 2p 3s 3p 6 3s 3p 6 8 0 Octet