Non-Metals

Non-metals included on the Periodic Table based on the IOUPAC 1985 standard
Click on the ABC Elements Link for Information about each chemical element in the Periodic Table
What are Non-metals? Define Non-metals
Non-metals are used as a term in Periodic Chemistry when classifying the chemical elements. Each element can usually be classified as a metal or a non-metal based on their general Physical and Chemical Properties. Non-metals  are any of the non-metallic elements within Groups 14,15 and 16 in the Periodic Table (see the List of Non-metals). Non-metallic elements exist, at room temperature, in two of the three States of Matter: Gases (such as oxygen) and Solids (such as carbon).
What are Non-metals? What elements are classified as Non-metals?
There is a great deal of variation among this group of 7 elements classified as Non-Metals. Three of the elements are gases and four are solids at normal room temperature. The Non-metals that are are gases are Hydrogen, Nitrogen and Oxygen. The Non-metals that are are solids are Carbon, Phosphorus, Selenium and Sulfer. The properties of non-metals are therefore not universal or as consistent as the metals.

What are Non-metals? Common Properties of Solid Non-metals
Elements described as the solid Non-metals have low melting points compared to the metals. They are poor conductors of heat and electricity, they are brittle solids, not ductile in their solid state – they cannot be rolled into wires or pounded into sheets. They are usually dull and therefore show no metallic luster and they do not reflect light. They also have a low density.

Common properties of Solid Non-metals
The elements classed as solid Non-metals therefore have some of the following properties in common:

  • Poor thermal conductors
  • Poor electrical conductors
  • Low Density
  • Dull, Brittle solids
  • Little or no metallic luster
  • High ionization energies
  • High electro-negativities

Non-metals List – Chemical Elements in the Periodic Table
The elements contained in the classification of Non-metals list are as follows:

  • Hydrogen – a gas
  • Carbon a solid
  • Nitrogen a gas
  • Oxygen a gas
  • Phosphorus a solid
  • Sulfur a solid
  • Seleniuma solid