in Organic Chemistry by (660 points)
edited by
Three allotropic forms and the temperature used to obtain the allotropic forms of sulphur

1 Answer

by (1.3k points)

The three allotropic forms of sulphur are Rhombic sulphur, Monoclinic sulphur, Plastic sulphur.

1. Rhombic Sulphur:

  • Stable form of a sulphur at room temperature
  • It consists of lemon yellow crystals that melts at 112.8oC
2. Monoclinic Sulphur:
  • It is heated in a china dish until it melts
  • The molten sulphur is cooled to the room temperature and two holes are pierced in the crust.
  • The liquid is poured out on removing the crust needle like crystals of sulphur are found.
3. Plastic Sulphur:
  • When sulphur is heated, plastic sulphur melts at 119oC and a clear yellow mobile liquid is obtained
  • If the substance is heated further to 160oC, it produces a thick viscous liquid.
  • If the hot liquid sulphur is poured into a cold water, it produces a soft, sticky rubber-like material. This material is called plastic sulphur.