Nonmetal is a term used in chemistry when classifying the chemical elements. On the basis of their general physical and chemical properties, every element in the periodic table can be termed either a metal or a non-metal. (A few elements with intermediate properties are referred to as metalloids.) The elements generally regarded as nonmetals are: hydrogen (H) In Group 14: carbon (C) In Group 15 (the pnictogens): nitrogen (N), phosphorus (P) Several elements in Group 16, the chalcogens: oxyge… (More on Non-metal)