Carbon is the element that has the atomic symbol C and the atomic number 6. It is found in allotropes such as diamond, graphite and glassy carbon. It is also the simplest element and can be formed into nanostructured forms such as carbon nanotubes and fullerenes.
Tetrafluoromethane – chemical formula (CF4)
In its natural form, tetrafluoromethane is an inert gas that can be used for a variety of purposes. It is a refrigerant and can be used to cool metals in the presence of oxygen.
CF4 is an organic compound with high stability due to its carbon-fluorine bonds. It has a bonding energy of 515 kJmol-1.
It can be used as a cooling agent, and it has a lower melting point than most other perfluorocarbons. It can also be used as a lubricant and an anti-freeze.
Tetrafluoromethane is inert to acid, hydroxide and oxidants at room temperature. It does not react with copper, nickel, tungsten and other transition metals below 900 degrees C.
At a higher temperature, tetrafluoromethane decomposes at the carbon arc to produce toxic fluoride. This process is dangerous, and should be avoided.
Chemically, tetrafluoromethane can be prepared in the laboratory by the reaction of carbon with hydrogen fluoride or difluoro dichloromethane. Alternatively, it can be synthesized by the direct reaction of fluorocarbon with sulfur tetrafluoride.
CF4 is used as an etching gas for plasma treatment and other metallurgical processes, particularly in the microelectronic industry. It is a relatively inexpensive plasma etching gas and has been in demand for some time.