Wikispace+of+Elements

= 1st Period =

H-1
He-4 Li-7 Be-9 B-11 C-12 N-14 O-16 F-19 Ne-20 Na-23 Mg-24 Al-27 Si-28 P-31 S-32 Cl-35 Ar-40

=2nd Period= Hydrogen-1 Helium-4 Lithium-7 Beryllium-9 Boron-11 Carbon-12 Nitrogen-14 Oxygen-16 Fluorine-19 Neon-20 Sodium-23 Magnesium-24 Aluminum-27 Silicon-28 Phosphorus-31 Sulfur-32 Chlorine-35 Argon-40

Example-1000