Periodic Table of Elements

1A2A3B4B 5B6B7B8 1B2B 3A4A5A6A 7A8A
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Cs Ba * Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra ** Rf Db Sg Bh Hs Mt Ds Uuu Uub Uut Uuq Uup Uuh Uus Uuo
* La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
** Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
The Periodic Table first discovered in 1869 by Dmitry I. Mendeleyev is a way of presenting all the elements so as to show their similarities and differences. The elements are arranged in increasing order of atomic number (Z) as you go from left to right accross the table. The horizontal rows a called periods and the vertical rows, groups. (http://www.chemicool.com/)
     Alkali Metals      Alkali Earth Metals
 Transition Metals  Other Metals
 Metalloids  Non-metals
 Halogens  Noble Gases
 Lanthanide Series  Actinide Series