Boron oxide (B2O3) is a compound formed by the chemical bonding of boron and oxygen. It is used in the production of glass and ceramics due to its high melting point.
| IUPAC Name | Boron oxide |
| Molecular Formula | B2O3 |
| CAS Number | 1303-86-2 |
| Synonyms | Triboron trioxide, Boric oxide, Boron(III) oxide |
| InChI | InChI=1S/B2O3/c3-1-5-2(4)6-1 |
Boron Oxide Properties
Boron Oxide Formula
The chemical formula of boric oxide is B2O3. It represents the ratio of boron atoms to oxygen atoms in the compound. The subscript numbers indicate that there are two boron atoms and three oxygen atoms present in each molecule of boric oxide.
Boron Oxide Molar Mass
The molar mass of boric oxide can be calculated by adding the atomic masses of its constituent elements. Boron has an atomic mass of 10.81 g/mol, while oxygen has an atomic mass of 16.00 g/mol. By multiplying the atomic masses by the respective number of atoms and summing them up, the molar mass of boric oxide is determined to be 69.62 g/mol.
Boron Oxide Boiling Point
Boric oxide has a high boiling point of approximately 1,860 degrees Celsius. This means that at normal atmospheric pressure, it requires significant energy to convert boric oxide from its liquid state to a gaseous state.
Boron Oxide Melting Point
The melting point of boric oxide is around 450 degrees Celsius. At this temperature, the solid boric oxide transitions into a liquid state. Its relatively low melting point makes it suitable for various industrial applications.
Boron Oxide Density g/mL
Boric oxide exhibits a density of about 2.46 g/mL. Density refers to the mass per unit volume of a substance. The density of boric oxide indicates that it is relatively dense, allowing it to sink in most liquids.
Boron Oxide Molecular Weight
The molecular weight of boric oxide, also known as its molar mass, is 69.62 g/mol. This value represents the mass of one mole of the compound and is useful for calculating the amount of boric oxide in a given sample.
Boron Oxide Structure
Boric oxide has a unique structure, featuring a network of trigonal planar BO3 units. The boron atoms are surrounded by three oxygen atoms in a triangular arrangement. This arrangement gives boric oxide its characteristic properties and stability.
Boron Oxide Solubility
Boric oxide is insoluble in water and most organic solvents. It has limited solubility in acids, such as sulfuric acid and hydrochloric acid. This low solubility contributes to its stability and usefulness in various applications, such as glass and ceramic production.
| Appearance | White solid |
| Specific Gravity | 2.46 g/mL |
| Color | White |
| Odor | Odorless |
| Molar Mass | 69.62 g/mol |
| Density | 2.46 g/mL |
| Melting Point | 450°C |
| Boiling Point | 1,860°C |
| Flash Point | Not applicable |
| Water Solubility | Insoluble |
| Solubility | Limited solubility in acids, such as sulfuric acid and hydrochloric acid |
| Vapour Pressure | Not applicable |
| Vapour Density | Not applicable |
| pKa | Not applicable |
| pH | Not applicable |
Please note that certain properties such as flash point, vapor pressure, vapor density, pKa, and pH are not applicable or have not been reported for boric oxide.
Boron Oxide Safety and Hazards
Boric oxide poses certain safety and hazard considerations. Direct contact with boric oxide powder or dust can irritate the skin, eyes, and respiratory system. It is important to handle it with care and use appropriate personal protective equipment such as gloves and goggles. Inhaling boric oxide particles may cause respiratory irritation, so it is advised to work in well-ventilated areas. In case of accidental ingestion, medical attention should be sought immediately. Boric oxide is non-flammable and does not possess a flash point. As with any chemical substance, it is recommended to follow proper handling and storage guidelines to ensure safe usage.
| Hazard Symbols | Not classified |
| Safety Description | Avoid contact with skin and eyes. Use in a well-ventilated area. Wear protective equipment. |
| UN IDs | Not applicable |
| HS Code | 2810.00.2000 |
| Hazard Class | Not classified |
| Packing Group | Not applicable |
| Toxicity | Low to moderate toxicity. May cause irritation upon contact or inhalation. |
Please note that boric oxide is not assigned hazard symbols, UN IDs, hazard class, or packing group. It is important to follow general safety guidelines and practices when handling and using boric oxide to minimize the risk of exposure and ensure safe usage.
Boron Oxide Synthesis Methods
Various methods allow for the synthesis of boric oxide. One widely used approach involves heating elemental boron in the presence of oxygen or air to create boric oxide. Another method entails reacting boron halides, such as boron trichloride (BCl3) or boron tribromide (BBr3), with water, resulting in the formation of boric oxide.
Additionally, boron-containing compounds like boron nitride or boron trisulfide can undergo hydrolysis with water to produce boric oxide. The thermal decomposition of borates, such as sodium borate or borax, when subjected to heat, also yields boric oxide.
It is important to note that the choice of a specific synthesis method depends on the desired purity, quantity, and application of boric oxide. Each method offers advantages and may be suitable for different situations.
Boron Oxide Uses
Boric oxide finds diverse applications in various industries. Here are some of its uses:
- Glass and Ceramic Production: Boric oxide is a key ingredient in the manufacture of glass and ceramics. It imparts desirable properties such as thermal resistance, transparency, and durability to glass products.
- Flame Retardants: Manufacturers utilize boric oxide as a flame retardant in materials like textiles, plastics, and wood products. Boric oxide reduces the flammability of these materials, ensuring enhanced safety.
- Borosilicate Glass: Boric oxide plays a vital role as a component in borosilicate glass, renowned for its low thermal expansion and high heat resistance. Industries employ this type of glass in laboratory equipment, cookware, and high-end optical devices.
- Specialty Fibers: The production of specialty fibers, including boron fiber and boron nitride fiber, incorporates the use of boric oxide. These fibers possess exceptional mechanical and thermal properties, making them suitable for aerospace, automotive, and high-tech industries.
- Boron-based Chemicals: Boric oxide serves as a precursor for the synthesis of various boron-based chemicals, such as borates and boron hydrides. These chemicals find applications in agriculture, pharmaceuticals, and energy storage systems.
- Fluxes and Welding Agents: Boric oxide reduces the melting point of materials and improves their flowability, making it an effective flux in metallurgical processes. It enhances the bonding of metal surfaces when used as a welding agent.
- Catalysts: Chemical reactions benefit from boric oxide-based catalysts, as they promote desirable reactions and increase reaction rates.
- Semiconductor Industry: Boric oxide plays a crucial role in the production of semiconductors. It acts as a dopant material to actively modify the electrical properties of silicon.
Boric oxide’s wide range of applications showcases its versatility and importance in various industries, contributing to advancements in technology, safety, and materials science.
Questions:
Q: What is the oxidation state of boron in B2O3?
A: The oxidation state of boron in B2O3 is +3.
Q: What is the empirical formula of boron oxide?
A: The empirical formula of boric oxide is B2O3.
Q: When will boron surface concentration affect oxide growth rate?
A: Boron surface concentration will affect oxide growth rate when it acts as a dopant or catalyst in the oxidation process.
Q: What is boron oxide boria?
A: Boric oxide, also known as boria, is a compound with the chemical formula B2O3.
Q: What is boron’s oxidation number?
A: Boron typically has an oxidation number of +3.
Q: Will boron slow oxidation in oxygen-deprived materials?
A: Boron does not slow oxidation in oxygen-deprived materials as it requires oxygen to form boric oxide
Q: What is the oxidation state of boron in HBO2 in CuO?
A: The oxidation state of boron in HBO2 is +3.
Q: How many moles of B2O3 can be formed?
A: The number of moles of B2O3 formed depends on the amount of reactants used in the reaction.
Q: Is B2O3 ionic or molecular?
A: B2O3 is an ionic compound.
Q: Which pair is listed in order of increasing basicity? PBO < SiO2 B2O3 < Li2O
A: The pair listed in order of increasing basicity is B2O3 < Li2O < PBO < SiO2.
Q: B2H6 + O2 → B2O3 + H2O, is this equation balanced?
A: No, the equation is not balanced. It requires adjustments to achieve a balanced equation.
Q: How much boron can be obtained from 210.0 lbs of B2O3?
A: The amount of boron obtained from 210.0 lbs of B2O3 depends on the molar mass and stoichiometry of the reaction.