Borax pentahydrate, also known as sodium borate pentahydrate or simply borax, is a crystalline form of borax that contains five molecules of water (H2O) per molecule of sodium borate. Here are some key points about borax pentahydrate:
1. **Chemical Composition**: The chemical formula of borax pentahydrate is Na2B4O7?5H2O. It consists of sodium (Na), boron (B), oxygen (O), and water (H2O) molecules.
2. **Physical Properties**:

? Borax pentahydrate appears as colorless or white crystals.

? It has a melting point of around 75?C and begins to lose its water of crystallization above this temperature.

? It is soluble in water, and the solution has alkaline properties.

? Borax pentahydrate is commonly used in its powdered form.
3. **Uses**:

? **Cleaning and Laundry**: Borax pentahydrate is commonly used as a household cleaner and laundry booster. It helps to soften water, remove stains, and deodorize fabrics.

? **Pesticide**: It is used in some pesticide formulations, particularly as an insecticide and insect repellent.

? **Fire Retardant**: Borax pentahydrate is used as a component in fire retardant formulations for wood and cellulose materials.

? **Crafts and DIY Projects**: It is used in various craft projects, such as making slime or as a flux in soldering.

? **Preservative**: Borax pentahydrate is used as a preservative in some products to inhibit the growth of fungi, mold, and bacteria.

? **Metallurgy**: In metallurgical applications, borax is used as a flux to help facilitate the soldering, brazing, and welding processes.
4. **Safety**:

? While borax is considered relatively safe for general use, it is important to handle it with care, avoid inhaling the dust, and keep it away from children and pets.

? Ingestion of large amounts of borax can be harmful, so it should not be ingested.
5. **Environmental Impact**:

? Borax pentahydrate is a naturally occurring mineral and is considered relatively environmentally friendly compared to some synthetic chemicals. However, it should still be used responsibly and disposed of properly.
Borax pentahydrate is a versatile compound with various household, industrial, and commercial applications due to its cleaning, preservative, and fire-retardant properties.