<Tr> <Td_colspan="2"> Infobox references </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> </Tr> <P> Carbon tetrachloride, also known by many other names (the most notable being tetrachloromethane, also recognized by the IUPAC, carbon tet in the cleaning industry, Halon - 104 in firefighting, and Refrigerant - 10 in HVACR) is an organic compound with the chemical formula CCl . It was formerly widely used in fire extinguishers, as a precursor to refrigerants and as a cleaning agent . It is a colourless liquid with a "sweet" smell that can be detected at low levels . It has practically no flammability at lower temperatures . </P> <P> Carbon tetrachloride was originally synthesized by the French chemist Henri Victor Regnault in 1839 by the reaction of chloroform with chlorine, but now it is mainly produced from methane: </P>

What is the formula for carbon tetrachloride a. ccl b. ccl2 c. ccl3 d. ccl4
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