Boron trichloride (BCl3) is a compound with three chlorine atoms bonded to a boron atom. It is used in various industrial processes, such as catalysts and as a reagent in organic synthesis.
| IUPAC Name | Boron trichloride |
| Molecular Formula | BCl3 |
| CAS Number | 10294-34-5 |
| Synonyms | Trichloroborane; Boron(III) chloride, Borane trichloro-, Trichloroboron |
| InChI | InChI=1S/BCl3/c2-1(3)4 |
Boron Trichloride Properties
Boron Trichloride Formula
The formula of boron chloride is BCl3, representing a boron atom bonded to three chlorine atoms. It is a simple and straightforward molecular formula that describes the composition of this compound.
Boron Trichloride Molar Mass
The molar mass of boron chloride can be calculated by adding the atomic masses of its constituent elements. Boron has an atomic mass of approximately 10.81 grams per mole, and each chlorine atom has an atomic mass of about 35.45 grams per mole. Therefore, the molar mass of BCl3 is approximately 117.17 grams per mole.
Boron Trichloride Boiling Point
Boron chloride has a relatively low boiling point compared to many other compounds. It boils at around -15.7 degrees Celsius or 3.77 degrees Fahrenheit. This means that at temperatures above this point, boron chloride transitions from a liquid to a gas phase.
Boron Trichloride Melting Point
The melting point of boron chloride is relatively low. It melts at approximately -107.5 degrees Celsius or -161.5 degrees Fahrenheit. At temperatures below this point, the compound changes from a solid to a liquid state.
Boron Trichloride Density g/mL
The density of boron chloride is approximately 1.38 grams per milliliter. This value indicates the mass of the compound per unit volume. It is useful for determining the behavior of boron chloride in various applications and understanding its physical properties.
Boron Trichloride Molecular Weight
The molecular weight of boron chloride is approximately 117.17 grams per mole. This value represents the sum of the atomic masses of all the atoms in one molecule of the compound and is useful for various calculations, such as determining the amount of boron chloride in a given sample.
Boron Trichloride Structure
Boron chloride has a trigonal planar molecular structure. It consists of a boron atom at the center bonded to three chlorine atoms, arranged in a triangular shape. This structure contributes to the compound’s physical and chemical properties.
Boron Trichloride Solubility
Boron chloride exhibits low solubility in water. It is sparingly soluble, meaning it dissolves only to a limited extent in aqueous solutions. However, it is more soluble in organic solvents such as benzene and carbon tetrachloride. The solubility of boron chloride influences its behavior in different chemical reactions and industrial processes.
| Appearance | Colorless gas |
| Specific Gravity | 1.369 g/mL |
| Color | Colorless |
| Odor | Pungent |
| Molar Mass | 117.17 g/mol |
| Density | 1.38 g/mL |
| Melting Point | -107.5°C |
| Boiling Point | -15.7°C |
| Flash Point | Not applicable |
| Water Solubility | Reacts |
| Solubility | Soluble in organic solvents such as benzene and carbon tetrachloride |
| Vapor Pressure | 623 mmHg at 20°C |
| Vapor Density | 3.24 (air = 1) |
| pKa | Not applicable |
| pH | Not applicable |
Boron Trichloride Safety and Hazards
Boron chloride poses several safety and hazard considerations. It is corrosive and can cause severe burns to the skin, eyes, and respiratory tract upon contact. Inhaling its vapors may lead to respiratory irritation and lung damage. The compound is also highly reactive with water, releasing toxic hydrogen chloride gas. It is essential to handle boron chloride with caution, using appropriate personal protective equipment and ensuring adequate ventilation. In case of accidental exposure, immediate medical attention is necessary. Furthermore, proper storage and handling procedures should be followed to prevent the risk of fire, explosions, and the release of hazardous gases.
| Hazard Symbols | Corrosive (C) |
| Safety Description | Wear protective gloves/eye protection/face protection. Do not breathe dust/fume/gas/mist/vapors/spray. Handle in a well-ventilated area. |
| UN IDs | UN1741 |
| HS Code | 2827390000 |
| Hazard Class | 8 (Corrosive substances) |
| Packing Group | II |
| Toxicity | Highly toxic upon ingestion or inhalation. Can cause severe burns and respiratory irritation. Handle with extreme care. |
Boron Trichloride Synthesis Methods
One method of synthesizing boron chloride involves the reaction between boron oxide (B2O3) and carbon tetrachloride (CCl4) in the presence of a catalyst like aluminum chloride (AlCl3). B2O3 and CCl4 react at elevated temperatures, yielding boron chloride and carbon dioxide as byproducts.
Another approach is the direct reaction between boron and chlorine gas. Under controlled conditions, boron reacts with chlorine, resulting in the formation of boron chloride. This method necessitates careful handling of chlorine gas due to its hazardous nature.
Thionyl chloride (SOCl2) enables the synthesis of boron chloride by reacting boron with SOCl2 at elevated temperatures, resulting in the production of boron chloride and sulfur dioxide gas.
These synthesis methods provide viable routes for manufacturing boron chloride, both in laboratory and industrial settings. It is crucial to ensure proper safety measures during synthesis, such as working in well-ventilated areas and employing suitable protective equipment. This is important due to the hazardous nature of the reactants and products involved in the process.
Write Boron Trichloride Uses
Boron chloride finds extensive use in catalysis, semiconductor manufacturing, materials synthesis, and various other industries due to its unique chemical properties and versatility.
- Boron chloride (BCl3) finds application as a catalyst in various chemical reactions, particularly in organic synthesis. It facilitates the formation of carbon-carbon and carbon-heteroatom bonds in the production of pharmaceuticals, agrochemicals, and fine chemicals.
- BCl3 serves as a reagent in the synthesis of boron-based polymers, such as polyborazylene, which have applications in flame retardancy and high-temperature coatings.
- BCl3 facilitates the production of boron nitride, a material renowned for its exceptional thermal and chemical stability, widely applied in high-temperature applications and as a lubricant.
- The semiconductor industry employs BCl3 as a dopant to incorporate boron atoms into silicon crystals, thereby improving their electrical properties and rendering them suitable for electronic device usage.
- In metallurgy, BCl3 acts as a flux agent to eliminate oxide impurities during metal refining, consequently enhancing their purity.
- BCl3 plays a pivotal role in the manufacturing of boron carbide, a lightweight and tough material extensively utilized in the production of ceramic armor and cutting tools.
- BCl3 plays a crucial role in synthesizing numerous boron-containing compounds, including boron esters, boronic acids, and boranes. These compounds have extensive applications in chemical research and industrial processes.
- Within the petroleum industry, BCl3 serves as an additive to heighten the octane rating of gasoline.
It serves as a source of boron in the production of boron-containing glass, which has desirable optical and thermal properties
Questions:
Q: What is the formula for boron trichloride?
A: The formula for boron chloride is BCl3.
Q: Is boron trichloride polar?
A: Yes, boron chloride is a polar molecule due to the presence of a lone pair on the boron atom and the asymmetrical arrangement of chlorine atoms.
Q: What is the hybridization of boron in boron trichloride (BCl3)?
A: The hybridization of boron in BCl3 is sp2.
Q: What is the mass of a boron trichloride molecule?
A: The mass of a boron chloride (BCl3) molecule is approximately 117.17 grams per mole.
Q: What is the hybridization of boron trichloride?
A: The hybridization of boron in boron chloride (BCl3) is sp2.
Q: What happens when you mix boron trichloride and hydrogen?
A: When boron chloride (BCl3) is mixed with hydrogen (H2), they react to form boron and hydrogen chloride gas (HCl).
Q: Why does boron trichloride exist as a monomer while aluminum trichloride exists as a dimer?
A: The difference in size and electron density between boron and aluminum atoms causes boron chloride (BCl3) to exist as a monomer, while aluminum chloride (AlCl3) forms a dimer due to its ability to form coordinate bonds.
Q: Is BCl3 a Lewis acid?
A: Yes, BCl3 is a Lewis acid as it can accept an electron pair from a Lewis base.
Q: Is BCl3 ionic or covalent?
A: BCl3 is a covalent compound.
Q: Is BCl3 a covalent bond?
A: Yes, BCl3 consists of covalent bonds between boron and chlorine atoms.
Q: Is BCl3 a gas?
A: Yes, BCl3 is a gas at standard temperature and pressure (STP).
Q: Is BCl3 a polar or nonpolar molecule?
A: BCl3 is a polar molecule due to the uneven distribution of electron density caused by the asymmetrical arrangement of chlorine atoms around the boron atom.