Block

The classification of chemical elements as blocks is based on the most energetic orbitals of their electron shell. A block groups several groups of the periodic table together.

s-block

The s-subshell of the respective current main shell is filled. The block includes the 1st and 2nd group as well as the element helium. All s-elements except helium are highly reactive, metals of the s-block are strongly electropositive and have low melting and boiling points.

p-block

The p-block – p-subshells of the current main shell are filled – includes the 3rd to 8th main group (excluding helium). The reactivity of elements in a group generally decreases downwards.

d-block

Transition elements (excluding lanthanides and actinides) are grouped in the d-block. d-subshells hold 10 electrons each, all elements in this block are metals and they are referred to as “outer transition metals”.

f-block

Lanthanides and actinides (inner transition metals) are defined by the f-block. They have two valence electrons in the outermost main shell, their chemical differences are correspondingly small.

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 La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og

Legend

s-block p-block d-block f-block