An Introduction to Borax
We have been using borax for cleaning purposes for ages. It was 1st traced in dry lake beds in Tibet and remained the only source of it till 1776 then Italy became the principal source of it until the 1860s. The famous 20-mule team borax company started in Death Valley, California, the US in 1889. It ruled the borax market for a long time.
What is Borax?
Borax is a natural mineral and a salt of boric acid. It is also known as sodium borate, sodium tetraborate, or disodium tetraborate. It is an important boron compound. Several closely related minerals that differ in their crystal water content such as decahydrate, pentahydrate, and octahydrate salts are also referred to as borax. Even its anhydrous form is also referred to as borax.
The formula of Borax – As we know the term borax is used for many closely related crystals. So, it has various formulas depending upon its water of crystallization.
Structure of Borax
(image will be updated soon)
Properties of Borax
Physical Properties of Borax –
Its Molar Mass is 202.22 (anhydrous) and 381.38 (decahydrate).
It is a white-colored solid substance.
Its density is 2.4g/cm3 (anhydrous) and 1.73 g/cm3 (decahydrate).
Its melting point is 743 ℃ (anhydrous) and 75 ℃ (decahydrate).
It is soluble in water.
Its boiling point is 1,575℃ (anhydrous).
Chemical properties of Borax –
Borax reacts with acids and can be easily converted into boric acids which is a highly useful compound. The reaction is given below –
Na2B4O7·10H2O + 2HCl → 4B(OH)3 + 2NaCl + 5H2O
It is flammable and produces yellow-green flame.
It is very soluble in ethylene glycol and slightly soluble in acetone.
Reaction with sodium hydroxide –
Na2B4O7 + 7H2O + 2NaOH 🡪 4Na[B(OH)4]
Occurrence of Borax
Borax occurs naturally as deposits in seasonal lakes by their repeated evaporation. It is most commonly found in Turkey, Boron (California), Searles Lake, southwestern United States, the Atacama Desert in Chile, Bolivia, Tibet, and Romania, etc.
Uses of Borax
Few of the Uses of Borax are Listed Below –
As Cleaning Agent – Various properties of borax help to increase its cleaning power. It converts water into hydrogen peroxide during cleaning. It is highly basic so it makes the hot water basic which enhances the effectiveness of bleach or other cleaners.
As an Insect Killer – Borax stops the metabolic process of many organisms. This property of borax makes it a better disinfectant.
It is used in the test of diabetes mellitus.
It is used as a water softening agent.
For welding of iron and steel mixture of borax and ammonium chloride is used as a flux.
Boric Acid vs. Borax
Borax and Boric Acid are two boron chemicals that are related. Borax is a natural mineral that can be mined from the ground or collected from evaporating deposits. The refined chemical that arises from the processing of borax is boric acid (H3BO3). Borax is a boric acid salt. While the chemicals differ in several ways, both forms of the chemical will function for insect control and slime.
Where can I get Borax?
Borax can be found in laundry detergents, hand soaps, and some toothpaste. It is also in one of the following items:
Powdered hand soap
20 Mule Team Borax (pure borax)
Tooth bleaching formulations (check labels for borax or sodium tetraborate)
Some more uses of Borax
Borax has a lot of uses on its own, and it is included in a lot of other items. Here are a few examples of how borax powder and pure borax can be used in water:
Insecticide, used in roach-killing treatments and as a moth repellent (ten percent solution on wool)
Fungicide
Herbicide
Desiccant
Booster for laundry
Cleaner for the house
Agent for water softening
As a preservative, it is a food additive (banned in some countries)
Borax is used in a variety of other items, including:
Buffering solutions
Anti-flame agents
Bleaching toothpaste
Glass, ceramics, and pottery
Glazes made of enamel
This is a precursor to boric acid.
Green-colored flames, slime, and borax crystals are illustrations of science projects.
Chemistry of analysis bead test with borax
Welding flux for iron and steel
FAQs on Borax
1. What exactly is borax and what is its chemical name?
Borax is a naturally occurring mineral compound of boron. Chemically, it is known as sodium tetraborate decahydrate. It is typically found as a white, soft, crystalline solid that dissolves in water to form a slightly alkaline solution.
2. What is the chemical formula of borax and what does its structure look like?
The correct chemical formula for borax is Na₂[B₄O₅(OH)₄]·8H₂O. Its core structure contains the tetranuclear [B₄O₅(OH)₄]²⁻ unit. In this structure, two boron atoms are in a triangular geometry (sp² hybridised) and the other two are in a tetrahedral geometry (sp³ hybridised).
3. What is the main difference between borax and boric acid?
Borax and boric acid are related but distinct compounds. Borax is a salt (sodium tetraborate), while boric acid (H₃BO₃) is a weak acid. In fact, boric acid can be prepared by treating a hot, concentrated solution of borax with a strong acid like HCl or H₂SO₄.
4. Are borax and baking soda the same chemical?
No, they are completely different chemicals. Borax is sodium tetraborate, while baking soda is sodium bicarbonate (NaHCO₃). While both are white powders used in households, their chemical properties and primary uses are very different. Baking soda is mainly used in cooking and as a mild antacid, whereas borax is used in detergents, glasses, and pottery.
5. What is the Borax Bead Test and why is it important in chemistry?
The Borax Bead Test is a classic method used in qualitative analysis to identify certain metal ions. The process involves:
- Heating powdered borax on a platinum loop to form a clear, colourless glassy bead (sodium metaborate).
- Touching the hot bead to a small amount of the sample and reheating it.
- The metal ion in the sample forms a coloured metaborate, and the colour of the bead helps identify the metal. For example, a cobalt salt gives a deep blue bead.
6. Why does a solution of borax in water become alkaline?
An aqueous solution of borax is alkaline because it hydrolyzes in water. Borax is a salt of a strong base (NaOH) and a weak acid (H₃BO₃). When dissolved, it reacts with water to form sodium hydroxide and orthoboric acid. The presence of the strong base, NaOH, makes the overall solution alkaline.
7. What are the most important uses of borax?
Borax has several important industrial and laboratory applications, including:
- Manufacturing of heat-resistant borosilicate glass (like Pyrex).
- Production of enamels and glazes for pottery and ceramics.
- Acting as a flux for soldering and welding metals to remove oxide layers.
- As a primary material for the Borax Bead Test in chemical analysis.
- Use in some cleaning products and as a mild antiseptic.
8. What is borax commonly called in India?
In India, borax is commonly known as Suhaga. It is widely used in traditional practices, including Ayurvedic medicine and as a flux by goldsmiths to purify and solder gold.
