61. Which one of the following mineral does not contain oxygen ? A.Haematite B.Bauxite C.Cryolite D.Calcite
Answer: Option C Solution: Cryolite (Na3AlF6, sodium hexafluoroaluminate) does not contain oxygen. It occurs as glassy, colorless, white-reddish to gray-black prismatic monoclinic crystals. Cryolite is used as an insecticide and a pesticide. It is also used to give fireworks a yellow color.
