Carbon tetrachloride
| Names | |
|---|---|
| IUPAC names
Carbon tetrachloride
Tetrachloromethane | |
| Other names
Benziform, Benzinoform, Carbon chloride, Carbon tet, Freon-10, Refrigerant-10, Halon-104, Methane tetrachloride, Methyl tetrachloride, Perchloromethane, Tetraform, Tetrasol
| |
| Properties | |
| CCl4 | |
| Molar mass | 153.81 g/mol |
| Appearance | Colorless liquid |
| Odor | Chloroform-like |
| Density | 1.831 g/cm3 (-186 °C) 1.809 g/cm3 (-80 °C) 1.594 g/cm3 (20 °C) |
| Melting point | −22.92 °C (−9.26 °F; 250.23 K) |
| Boiling point | 76.72 °C (170.10 °F; 349.87 K) |
| 0.097 g/100 ml (0 °C) 0.081 g/100 ml (25 °C) | |
| Solubility | Miscible with most organic solvents |
| Vapor pressure | 11.94 kPa at 20 °C |
| Thermochemistry | |
| Std molar
entropy (S |
214.42 J·mol-1·K-1 |
| Std enthalpy of
formation (ΔfH |
-139.3 kJ/mol |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
2350 mg/kg |
| LC50 (Median concentration)
|
5400 ppm (mammal) 8000 ppm (rat, 4 hr) 9526 ppm (mouse, 8 hr) |
| Related compounds | |
| Related compounds
|
Dichloromethane Chloroform |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Carbon tetrachloride, also known as tetrachloromethane or carbon tet, is a compound with the chemical formula CCl4. It can be seen as either inorganic (halide of carbon) or organic (the simplest perchlorocarbon).
Contents
Properties
Chemical
Carbon tetrachloride does not burn in air, but can be oxidized at high temperatures in air to form the toxic phosgene.
- CCl4 + ½ O2 → COCl2 + Cl2
Careful addition of carbon tetrachloride to anhydrous hot (120-130 °C) sulfuric acid will yield phosgene, hydrochloric acid and pyrosulphuryl chloride.[1]
- 3 CCl4 + 2 H2SO4 → 3 COCl2 + 4 HCl + Cl2O5S2
CCl4 will dissolve iodine.
Potassium metal in the presence of carbon tetrachloride and traces of heptane or hexane forms a powerful shock-sensitive explosive material.[2]
Physical
Carbon tetrachloride is a colourless liquid with a strong ether-like smell. It is insoluble in water, but soluble in many organic solvents, such as benzene, carbon disulfide, chloroform, diethyl ether, ethanol, formic acid, isopropanol and naphtha. It boils at 76.72 °C and freezes at −22.92 °C.
Availability
Carbon tetrachloride used to be available in the past, but today it's hard to find, due to being toxic and carcinogenic. Most chemistry institutions have also phased out the use of CCl4 in favor of other less dangerous solvents.
"Fire extinguishing grenades" (sealed bulbs filled with carbon tetrachloride) can sometimes be bought as antiques.
Preparation
Carbon tetrachloride can be synthesized by chlorinating carbon disulfide at temperatures between 105 to 130 °C:
- CS2 + 3 Cl2 → CCl4 + S2Cl2
It can also be prepared by chlorinating chloroform in the presence of light.
Complete halogenation of methane with chlorine under UV light is the most common way of synthesizing the compound, used extensively in industry.
Projects
- Solvent for chlorinating reactions
- Make Carbon-Tet Explosive (CCl4 + Al powder)
Handling
Safety
Carbon tetrachloride is a toxic and carcinogenic compound, and is one of the most potent hepatotoxins (toxic to the liver).
Carbon tetrachloride has practically no flammability at lower temperatures, but will oxidize at high temperatures in air to yield poisonous phosgene.
Storage
Carbon tet should be stored in closed bottles, away from any heat source as well as oxidizers.
Disposal
Carbon tetrachloride is best neutralized with a modified Fenton's reagent solution.[3] Perform this process outside or in a fumehood to avoid aerosolizing carbon tet, which is toxic and carcinogenic.
A more accessible method involves the use of copper(II) acetate.[4]
References
- ↑ http://www.prepchem.com/synthesis-of-phosgene/
- ↑ https://www.youtube.com/watch?v=psUc_oBXE6c
- ↑ http://www.sciencedirect.com/science/article/pii/S0304389402000687
- ↑ http://www.researchgate.net/publication/221866609_Investigation_of_Carbon_Tetrachloride_Destruction_by_Copper_Acetate
