Boron tribromide (BBr3) is a chemical compound used as a catalyst in various reactions. It consists of one boron atom and three bromine atoms.
| IUPAC Name | Boron tribromide |
| Molecular Formula | BBr3 |
| CAS Number | 10294-33-4 |
| Synonyms | Tribromoborane; Boron bromide; Boron(III) bromide; Bromoboron; Boron tribromide, [B(Br)3]; Tribromo-borane |
| InChI | InChI=1S/3BrH.B/h3*1H;/q;;;+3/p-3 |
Boron Tribromide Properties
Boron Tribromide Formula
The formula of boron bromide is BBr3. It consists of one boron atom and three bromine atoms. This chemical compound is formed by the combination of boron and bromine.
Boron Tribromide Molar Mass
The molar mass of boron bromide (BBr3) can be calculated by adding the atomic masses of boron and three bromine atoms. Boron has an atomic mass of approximately 10.81 grams per mole, and bromine has an atomic mass of around 79.90 grams per mole. Thus, the molar mass of BBr3 is approximately 250.60 grams per mole.
Boron Tribromide Boiling Point
Boron bromide has a relatively low boiling point. It starts to boil at around 91 degrees Celsius (196 degrees Fahrenheit). At this temperature, the compound undergoes a phase change from a liquid to a gas, releasing vapors of BBr3.
Boron Tribromide Melting Point
The melting point of boron bromide is relatively high. It begins to melt at around -46 degrees Celsius (-51 degrees Fahrenheit). At this temperature, the solid compound transforms into a liquid state.
Boron Tribromide Density g/mL
Boron bromide has a density of approximately 2.63 grams per milliliter (g/mL). This density indicates the mass of BBr3 present in one milliliter of the compound. It is a measure of the compactness or concentration of the substance.
Boron Tribromide Molecular Weight
The molecular weight of boron bromide (BBr3) is calculated by summing up the atomic masses of boron and three bromine atoms. The molecular weight of BBr3 is approximately 250.60 grams per mole.
Boron Tribromide Structure
The structure of boron bromide consists of one boron atom bonded to three bromine atoms. The arrangement forms a trigonal planar geometry, where the boron atom lies in the center, and the three bromine atoms are evenly distributed around it.
Boron Tribromide Solubility
Boron bromide is a highly reactive compound and is generally not very soluble in water. It tends to react with water to form hydrobromic acid and boric acid. However, BBr3 is soluble in organic solvents such as chloroform, carbon tetrachloride, and carbon disulfide.
| Appearance | Colorless liquid |
| Specific Gravity | 2.63 g/mL |
| Color | Colorless |
| Odor | Pungent |
| Molar Mass | 250.60 g/mol |
| Density | 2.63 g/mL |
| Melting Point | -46°C |
| Boiling Point | 91°C |
| Flash Point | Not applicable |
| Water Solubility | Reacts |
| Solubility | Soluble in organic solvents such as chloroform, CCl4, and carbon disulfide |
| Vapor Pressure | 78 mmHg |
| Vapor Density | 6.52 (air=1) |
| pKa | Not applicable |
| pH | Not applicable |
Boron Tribromide Safety and Hazards
Boron bromide poses certain safety hazards and precautions should be taken when handling this compound. It is corrosive to skin, eyes, and respiratory system. Direct contact can cause burns and severe irritation. Inhalation of its vapors may result in respiratory discomfort. It reacts vigorously with water, releasing toxic fumes. Therefore, it should be handled in a well-ventilated area and appropriate personal protective equipment, such as gloves and goggles, should be worn. It should be stored away from moisture and incompatible substances. In case of exposure, immediate medical attention is necessary. Proper safety protocols and guidelines must be followed to minimize risks associated with boron bromide.
| Hazard Symbols | Corrosive, Dangerous When Wet |
| Safety Description | Avoid contact with skin, eyes, and clothing. Use in a well-ventilated area. Wear protective gloves and goggles. |
| UN IDs | UN3264 |
| HS Code | 2811.19.9000 |
| Hazard Class | 8 |
| Packing Group | II |
| Toxicity | Toxic by inhalation and if swallowed; causes severe skin burns and eye damage. |
Boron Tribromide Synthesis Methods
Boron bromide can be synthesized through various methods. One common method involves the reaction between boron oxide (B2O3) and bromine (Br2). The reaction takes place in the presence of a catalyst, such as carbon or aluminum, at elevated temperatures. The resulting reaction produces boron bromide along with the liberation of oxygen gas.
Another method involves the reaction between boron trichloride (BCl3) and bromine. This reaction occurs at room temperature and forms boron bromide and chlorine gas as byproducts.
To prepare boron bromide, one can react boron with excess bromine in a controlled environment, requiring high temperatures and careful control of the reaction conditions.
Another method involves synthesizing boron bromide by reacting boron hydrides, such as diborane (B2H6) or borane (BH3), with hydrogen bromide (HBr). This reaction produces boron bromide and hydrogen gas as products.
Keep in mind that these synthesis methods require caution due to the highly reactive nature of boron bromide. Proper safety protocols, such as wearing appropriate protective equipment and working in a well-ventilated area, should be followed during the synthesis process.
Boron Tribromide Uses
Boron bromide (BBr3) has several important uses across various industries. Here are some key applications:
- Catalyst: BBr3 actively catalyzes organic synthesis reactions, enabling processes such as acylation, alkylation, and halogenation reactions.
- Chemical Intermediates: BBr3 acts as a precursor in producing other boron compounds, synthesizing boron-containing reagents, boronic acids, and boron-based polymers.
- Polymerization: BBr3 actively participates in polymerization reactions, particularly in producing polymers like polyethylene and polypropylene, serving as a Lewis acid catalyst.
- Doping Agent: The semiconductor industry actively uses BBr3 as a doping agent, modifying the electrical properties of silicon for electronic device suitability.
- Gas Detection: BBr3 actively reacts with specific gases like ammonia, making it suitable for gas detectors and sensors utilized in sensing and monitoring purposes.
- Laboratory Reagent: BBr3 actively serves as a reagent in various laboratory experiments and research, performing bromination reactions and acting as a source of bromine atoms in synthetic chemistry.
- Pharmaceutical Synthesis: The pharmaceutical industry actively utilizes BBr3 in the synthesis of certain drugs and pharmaceutical intermediates.
It is important to handle boron bromide with care, following proper safety protocols, due to its corrosive and reactive nature.
Questions:
Q: Which term describes the reactivity of boron tribromide (BBr3)?
A: Highly reactive.
Q: What is the formula for boron tribromide?
A: The formula for boron bromide is BBr3.
Q: How many atoms of boron are present in 3.24 grams of boron tribromide?
A: There are 0.053 moles of BBr3 in 3.24 grams, which corresponds to 0.159 moles of boron, or approximately 9.62 x 10^22 atoms.
Q: How many grams of boron tribromide can be produced from 3.49 grams of bromine?
A: The molar mass of BBr3 is 250.60 g/mol. Thus, approximately 3.49 grams of bromine can produce around 3.34 grams of boron bromide.
Q: What is the name of the compound with the formula BBr3?
A: The compound with the formula BBr3 is called boron bromide.
Q: Is boron tribromide polar or nonpolar?
A: Boron bromide is a polar compound.
Q: What is the electronic geometry of BBr3?
A: The electronic geometry of BBr3 is trigonal planar.
Q: What is the Lewis structure for BBr3?
A: In the Lewis structure of BBr3, there is one boron atom in the center surrounded by three bromine atoms.
Q: How many peaks in BBr3?
A: Boron bromide (BBr3) exhibits one peak in its NMR spectrum.