**Boron Nitride**

When boron reacts with nitrogen, the compound formed is boron nitride (BN). Boron nitride is a binary compound consisting of boron and nitrogen atoms. It has a similar structure to carbon in diamond, where each atom is bonded to four neighboring atoms in a tetrahedral arrangement.

**Formation of Boron Nitride**

The reaction between boron and nitrogen to form boron nitride can occur at high temperatures and pressures. One common method of synthesizing boron nitride is through the reaction of boron oxide (B2O3) with ammonia (NH3):

B2O3 + 2NH3 → 2BN + 3H2O

In this reaction, boron oxide reacts with ammonia to form boron nitride and water. Boron oxide acts as a source of boron, while ammonia provides nitrogen. The reaction is typically carried out at temperatures exceeding 800°C.

**Properties of Boron Nitride**

Boron nitride exists in various forms, including hexagonal boron nitride (h-BN) and cubic boron nitride (c-BN). Hexagonal boron nitride has a layered structure similar to graphite and is often referred to as "white graphene" due to its similar properties.

Some key properties of boron nitride include:

1. High melting point: Boron nitride has a high melting point of around 3000°C, making it suitable for high-temperature applications.

2. Electrical insulator: Boron nitride is an excellent electrical insulator, meaning it does not conduct electricity.

3. Thermal conductor: While boron nitride is an electrical insulator, it is a good conductor of heat. This property makes it useful in applications requiring high thermal conductivity.

4. Chemical inertness: Boron nitride is chemically inert, meaning it does not easily react with other substances. This property makes it resistant to corrosion and oxidation.

5. Lubricating properties: Boron nitride has low friction and excellent lubricating properties, similar to graphite. It is often used as a dry lubricant in high-temperature applications.

Overall, boron nitride is a versatile compound with a wide range of applications, including as a high-temperature lubricant, thermal insulator, and electrical insulator. Its unique combination of properties makes it useful in various industries, including electronics, aerospace, and energy.