group 15

The elements of group 15 (formerly called group Va in North America and Vb in Europe) include the gas nitrogen, the nonmetal phosphorus, the metalloid arsenic, the metals antimony and bismuth, , and the recently discovered (and presumably metallic) ununpentium. All have high ionization potentials. The lighter members, nitrogen and phosphorus, are distinctly electronegative. The so-called nitrogen group, also called the pnictogens, contains a very high number of allotropes following the trend from non-metallic to metallic forms. Nitrogen, like the first member of any chemical group, behaves differently than the other members; forming, for example, stable multiple bonds and possessing sufficient electronegativity to form hydrogen bonds; further, nitrogen's oxides are irregular with the rest of the group. The atoms of the elements in group 15 have 5 valence electrons.