Borax is the trade name for Boron Salt. Borax is a white crystal that is easily soluble in water. Borax has a multitude of uses, both in detergents, softeners, soaps,... and in jewellery as a flux for soldering gold, silver, etc. It is also used in the manufacture of glass and paint components.
IDENTIFICATION AND PROPERTIES
SynonymsDisodium tetraborate decahydrate, Sodium tetraborate decahydrate, Sodium tetraborate decahydrate
- Appearance (20ºC; 1013 hPa): White crystalline solid (powder or granular)
- Odour: Odourless
- pH (20ºC): 9.3 (solution at 0.1%) 9.2 (solution at 1.0%) 9.3 (solution at 4.7%)
- Melting point: 741ºC
- Boiling point: 1575ºC
- Vapour pressure (50ºC): <300 kPa
- Relative density (20ºC): 1,73 g/cm3
- Solubility in water (20ºC): 4.7%
- Solubility in water (100ºC): 65.6%
- Partition coefficient n-octanol/water (Log Pow) (20ºC): -0.757
- Decomposition temperature: -95ºC
- Explosive properties: Non-explosive
- Oxidising properties: Non-combustive
You can see the uses and properties in more detail in this section: Uses of Borax.
- IN DETERGENTS
Borax is one of the ingredients of which most soaps, detergents and fabric softeners are composed. Borax is used because as an amphoteric compound (it reacts with acids and bases), it is a good pH regulator, as well as softening carbonates in water, allowing for greater cleanliness.
Borax is sometimes used as a detergent booster. Especially in case of using a very basic detergent, an enhancer such as borax is used to improve the properties of the detergent. Borax is also used for the manufacture together with sodium carbonate of household detergents.
- IN JEWELLERY:
In gold and silver casting, borax is used to dissolve the oxides formed during the heating of gold and silver. It allows the molten material to flow over the mould and retains its lustre.
MAKING A SLIME WITH BORAX (experiment)
One of the most common experiments or crafts among young people is the making of a slime, or sticky dough. The most common and most effective way to make a slime is with Borax.
Borax is also used in the manufacture of glass, enamels, foliar fertilisers and paint components.