Toluene is a colorless liquid with a sweet, pungent odor. It is widely used as a solvent, as well as in the production of chemicals, dyes, and pharmaceuticals. It can be harmful if ingested or inhaled in large quantities.
| IUPAC Name | Methylbenzene |
| Molecular Formula | C7H8 |
| CAS Number | 108-88-3 |
| Synonyms | Toluol, Phenylmethane, Methylbenzene, Tolu-sol, Toluene, Methyl benzene, Toluol Oil, Anisen, Antisal 1A, Benzene, Methyl-, Mono-Methylbenzene |
| InChI | InChI=1S/C7H8/c1-7-5-3-2-4-6-7/h2-6H,1H3 |
Toluene Properties
Toluene Structure
Toluene has a simple chemical structure, consisting of a benzene ring with a single methyl group attached to it. The molecule is planar and exhibits delocalized pi electron bonding. This unique structure makes toluene a useful starting material in the production of various chemicals, such as benzene and xylene, as well as in the synthesis of pharmaceuticals, dyes, and polymers.
Toluene formula
The chemical formula for toluene is C7H8, which represents the number and type of atoms present in the molecule. This formula is important in various industrial applications, as it can help predict the physical and chemical properties of the compound, such as its melting point, boiling point, and reactivity in different chemical reactions.
Toluene density g/ml
The density of toluene is approximately 0.87 grams per milliliter at standard temperature and pressure. This relatively low density is due to toluene’s low molar mass and molecular size. Toluene’s density is important in many industrial processes, as it can affect the solubility and reactivity of the compound in various chemical reactions.
Toluene molar mass
Toluene, with the molecular formula C7H8, has a molar mass of approximately 92.14 grams per mole. This value can be obtained by adding up the atomic masses of the constituent atoms in the molecule. Toluene’s relatively low molar mass makes it a volatile and highly mobile compound, which contributes to its use as a solvent in various industrial processes.
Toluene boiling point
Toluene has a boiling point of approximately 110.6 degrees Celsius at standard atmospheric pressure. This relatively low boiling point makes it easy to evaporate and use as a solvent in a variety of industrial applications, including as a diluent in paint and coatings, as well as in the production of synthetic fibers and rubber.
Toluene melting point
The melting point of toluene is around -95 degrees Celsius. This makes it a liquid at standard temperature and pressure, but it can be easily solidified by cooling it below its melting point. Toluene’s low melting point is due to the weak intermolecular forces of attraction between its molecules, which are primarily van der Waals forces.
Toluene molecular weight
Toluene’s molecular weight is 92.14 grams per mole, which is calculated by summing up the atomic masses of the atoms in the molecule. This value is important in various industrial applications, as it can affect the physical and chemical properties of the compound, including its boiling point, melting point, and solubility in different solvents.
| Appearance | Colorless liquid |
| Specific Gravity | 0.866 |
| Color | Colorless |
| Odor | Sweet, pungent |
| Molar Mass | 92.14 g/mol |
| Density | 0.87 g/mL at 25°C |
| Melting Point | -95°C |
| Boiling Point | 110.6°C |
| Flash Point | 4.4°C |
| Water Solubility | 0.052 g/100 mL at 25°C |
| Solubility | Soluble in organic solvents |
| Vapour Pressure | 22 mmHg at 25°C |
| Vapour Density | 3.1 (air = 1) |
| pKa | 44 |
| pH | Not applicable |
Note: Some values may vary depending on the source and conditions of measurement.
Toluene Safety and Hazards
Methyl benzene can pose several safety hazards if handled improperly. It is flammable and may form explosive mixtures with air, so it should be kept away from heat, sparks, and flames. Inhalation of methyl benzene vapors can cause irritation to the respiratory system, headaches, dizziness, and drowsiness, and chronic exposure can lead to neurological and behavioral changes. Prolonged or repeated skin contact can cause dermatitis. Methyl benzene has also been shown to have reproductive and developmental effects in animals and is classified as a Category 2 carcinogen. Proper protective equipment and ventilation should be used when handling methyl benzene to minimize exposure to its hazardous effects.
| Hazard Symbols | Xn, F |
| Safety Description | Keep away from heat/sparks/open flames/hot surfaces. Use explosion-proof electrical/ventilating/lighting equipment. Keep container tightly closed. Do not breathe vapor. Wear protective gloves/clothing/eye protection/face protection. |
| UN IDs | UN 1294 |
| HS Code | 2902.2 |
| Hazard Class | 3 |
| Packing Group | II |
| Toxicity | Methyl benzene can cause irritation to the eyes, nose, and throat, as well as headache, dizziness, and drowsiness. Chronic exposure can result in neurological and behavioral changes. Prolonged or repeated skin contact may cause dryness, cracking, and dermatitis. Methyl benzene has been shown to have reproductive and developmental effects in animals. It is classified as a Category 2 carcinogen by the International Agency for Research on Cancer (IARC). Proper protective equipment and ventilation should be used when handling methyl benzene to minimize exposure. |
Toluene Synthesis Methods
The chemical industry commonly produces methylbenzene through a number of synthetic methods, including catalytic reforming of naphtha, catalytic cracking of crude oil fractions, and methylbenzene disproportionation.
Catalytic reforming of naphtha is one of the most commonly used methods of methylbenzene production, as it yields a mixture of aromatic hydrocarbons that can be separated and purified. The process involves reacting naphtha with a catalyst in the presence of hydrogen, which produces a mixture of aromatics that includes methylbenzene.
Catalytic cracking of crude oil fractions can also produce methyl benzene, along with other aromatic and non-aromatic hydrocarbons. This process involves reacting high-boiling point crude oil fractions with a catalyst at high temperature and pressure. This breaks down the molecules into smaller fragments that can be separated and purified.
Methylbenzene disproportionation is a process that converts methyl benzene into a mixture of benzene and xylenes. The reaction is typically carried out at a high temperature and pressure in the presence of a catalyst and can be used to produce high-purity benzene and xylenes for use in a variety of industrial applications.
Toluene Uses
Methylbenzene has a variety of industrial and commercial uses, owing to its unique properties as a volatile, colorless liquid with a distinct odor. Some of its major applications include:
- Solvent manufacturers widely use toluene as a solvent in the manufacture of paints, coatings, adhesives, and other products. It is prized for its ability to dissolve a wide range of organic compounds, as well as its relatively low toxicity and high evaporation rate.
- Toluene boosts the performance and efficiency of internal combustion engines, so it is used as a high-octane component in gasoline.
- Manufacturers use toluene as a key intermediate in the production of a variety of chemicals, including benzene, xylene, and various other aromatic compounds. These chemicals are used in the manufacture of plastics, synthetic fibers, rubber, and other materials.
- Some medical and pharmaceutical applications use toluene, including as a component of some topical medications and as a solvent for certain medical compounds.
- Researchers use toluene as a solvent and reactant in a variety of laboratory research applications, owing to its ability to dissolve and react with a wide range of organic compounds.
Questions:
Toluene to benzyl alcohol
A multistep process achieves the conversion of methyl benzene to benzyl alcohol. One common approach involves the following steps:
- Oxidation of methyl benzene to benzyl chloride: Methyl benzene can be oxidized to benzyl chloride using chlorine gas and a catalyst such as iron or aluminum chloride. This reaction involves the replacement of a hydrogen atom on the methyl group of methyl benzene with a chlorine atom.
- Hydrolysis of benzyl chloride to benzyl alcohol: Benzyl chloride can be hydrolyzed to benzyl alcohol using an aqueous solution of sodium hydroxide. This reaction involves the replacement of the chloride group on benzyl chloride with a hydroxyl group.
- Purification of benzyl alcohol: The resulting benzyl alcohol can be purified using distillation or other methods to remove any impurities.
Toluene to benzaldehyde
The conversion of methyl benzene to benzaldehyde can be achieved through a multistep process. One common approach involves the following steps:
- Oxidation of methyl benzene to benzyl alcohol: Methyl benzene can be oxidized to benzyl alcohol using an oxidizing agent such as potassium permanganate or chromic acid. This reaction involves the replacement of a hydrogen atom on the methyl group of methyl benzene with a hydroxyl group to form benzyl alcohol.
- Oxidation of benzyl alcohol to benzaldehyde: Benzyl alcohol can be further oxidized to benzaldehyde using an oxidizing agent such as potassium permanganate or sodium chlorite. This reaction involves the removal of the hydroxyl group on benzyl alcohol to form a carbonyl group on benzaldehyde.
- Purification of benzaldehyde: The resulting benzaldehyde can be purified using distillation or other methods to remove any impurities.