Borax (Na2B4O7 · 10h2o, sodium borate or sodium tetraborate decahydrate), formerly known as Tincal or Borax Veneziano, is an important boron compound. It is a soft white crystal, which dissolves easily in the water. If left exposed to dry air, it slowly loses hydration water and becomes a chalky white substance. The commercially sold borax is usually completely dehydrated.
Uses sodium borate
Borax is a substance that, at high temperature, is transformed into an insulating glass and therefore its main use is as an adjuvant paste in the welding.
In the same way it is used to create a vitreous insulating layer on earthling pottery. It is used in the production of enamel, glass and ceramic-reinforced pottery.
In analytical chemistry has found use in the past for the qualitative detection of the presence of a given ion in a compound through the so-called Sage to the pearl of Borax.
This method consists in merging some borax crystal into a small bead on which to adhere some crystal of the test compound and then immersing the pearl in the reducing region and then in the oxidizing region of the flame of a bunsen beak.
The ions present in the compound give to the pearl of the characteristic colours, indicative of their presence.