8. Carbon tetrachloride (pyrene)

Carbon tetrachloride (pyrene)

Preparations & reactions :

• CCl₄ is stable to heat and its vapours do not catch fire thus it is used as fire extinguisher.
• CCl₄ used as medicine for elimination of hook worms.

Freons (Polychlorofluoro alkane)

Nomenclature of Freons :

Freon is expressed as

Freon - cba

Where

a –  [Number of F-atoms]

b –  [1 + Number of H–atoms]

c –  [Number of C-atoms –1]

Example : C₂Cl₄F₂ is expressed as Freon-112

a = 2 ;    b = 1 + 0 ;   c = 2 – 1

cba = 112

• Freon is odourless, non-corrosive, non-toxic gas. It can easily be liquefied hence widely used as refrigerant.