A compound that contains only two elements is called a binary compound. In naming the compounds containing two elements, a metal and a nonmetal, the first element is named as such and the name of the second element, i.e., the more electronegative element changes its ending to –ide. For example,

  • NaCl is named as Sodium chloride
  • Cao is named as Calcium oxide
  • FeS is named as Iron sulphide
  • BaCl2 is named as Barium Chloride