This is a halogen element, lustrous solid, which volatilizing at ordinary temperatures into a blue-violet gas with an irritating odor. Ample amounts of this element are required by the human body for the proper function of the thyroid gland.
This is a non-metal and it is a structural element of all biomolecules and living beings. Three naturally occurring allotropes of this element are known to exist: amorphous, graphite and diamond.
This element is a noble gas which is gas at room temperature. It is characterized by its brilliant green and orange spectral lines. This noble gas is used in fluorescent light bulbs, luminous signs, high-speed photography.