Sodium Carbonate (also known as washed soda, soda ash, or soda crystals) is a water-soluble Sodium Carbonate salt. Pure Sodium Carbonate is a hygroscopic, odorless white powder (absorbs moisture from the air). It has a strong alkaline odor and dissolves in an alkaline aqueous solution. The application of Sodium Carbonate as a water softener is well known in the United States. Sodium Carbonate can be made from the ashes of many plants that grow in sodium-rich soils, such as Middle Eastern vegetation, Scottish seaweed, Spanish seaweed. The ash of these sodium-rich plants is so different from the lumber (used to make potash) that it was named “soda.” It is Synthesized in large quantities from salt (sodium chloride).

Sodium Carbonate Manufacturing

A.) From algae and plants Some “salt” (salt-tolerant) plants and algae can be used to make impure Sodium Carbonate. Land plants and algae are harvested and burned. The remainder of the ash should next be rinsed with water to create an alkaline solution, and then this final result is cooked to obtain the end products.

B.) Sodium Carbonate is presently produced exclusively by the Solvay technique. In this method, carbon dioxide and ammonia are injected into a cold saturated sodium chloride solution. Baking soda is formed as a result of the process. The solubility is exceedingly poor in the presence of sodium ions, and it precipitates practically entirely. Filtration removes it, and it is then burnt to generate Sodium Carbonate.

This technique’s components are readily available and affordable. Brine (NaCl), ammonia (NH3), and limestone are the three (CaCO3).

This technique produces CaCl2, which is an important by-product.

2NH3 + H2O + CO2 → (NH4)2CO3

(NH4)2CO3 + H2O + CO2 → 2NH4HCO3

Adding salt to a solution containing NH4 + and HCO3- will precipitate the most insoluble NaHCO3. Then it will be filtered out.

NH4HCO3 + NaCl → NH4Cl + NaHCO3

Na2CO3 is then produced by heating sodium bicarbonate.

2NaHCO3 → Na2CO3 + CO2 + H2O

The obtained CO2 gas can be reused. 

When anhydrous Sodium Carbonate is dissolved in water and recrystallized, washed soda crystals with ten molecules of water of crystallization are obtained.

Salt Cake: Aqueous solution of the salt and an adequate amount of concentrated sulfuric acid are added to the iron pan to heat this combination. The action of sodium chloride with sulfuric acid removes sodium sulphate , and the HCl vapour is kept. HCl acid is formed when the resultant HCl reacts with cold water. The leftover sulfuric acid is degraded and separated into steam when the mixture is heated further. On the other hand, sodium sulfate is produced as a hard solid. This salt cake is the hard solid that results from this process.

Properties of Sodium Carbonate 

Physical Properties :

• Its Molecular weight:- 105.99 g/mol.

• White crystalline solid 

• Soluble in water.

• Boiling point:-1600℃.

• Melting point: 851 ℃.

• Its density is 2.54 g/cm3.

• It is an odorless substance.

Chemical Properties of Sodium Carbonate – Na2CO3

1. Anhydrous Sodium Carbonate is thermally stable. It melts at 852 °C without decomposition.

 2. Sodium Carbonate aqueous solution is weakly alkaline because OH– (aq) ions are released by hydrolysis.

Na2CO3(s) + 2H2O(l) → H2CO3(aq) + 2Na+(aq) + 2OH–(aq)

3. Sodium Carbonate aqueous solution absorbs carbon dioxide from the air and produces sodium hydrogen carbonate.

Na2CO3(aq) + H2O + CO2(g) → 2NaHCO3(aq)

4. Sodium Carbonate releases carbon dioxide by reacting with weak vegetable acids such as lime juice.

Na2CO3(aq) + 2H+(aq) → 2Na+(aq) + H2O(l) + CO2(g)

Na2CO3(aq) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g)

Structure Of Sodium Carbonate

Each Sodium Carbonate molecule contains two sodium atoms, three oxygen atoms, and one carbon atom. The charge for each sodium cation is +1, but the net charge for polyatomic carbonate anions is 2. Therefore, Sodium Carbonate is a neutrally charged molecule

Sodium Carbonate is used in a variety of ways.

1) Sodium Carbonate softens water by eliminating Mg2+ and Ca2+ from it. When these ions are combined with carbonate ions, they create an insoluble solid precipitate. Soft water also lowers soap loss and improves the life of pipes and fittings by preventing corrosion.

2) Glass manufacture Sodium Carbonate functions as a flux for silica, decreasing the melting point of the combination and allowing the production of “soda-lime glass” without the need of specific components at a reduced cost.

3) Additives to Food: Sodium Carbonate is an acidity regulator, separator, leavening agent, and stabilizer used as a food additive .

4) Other Applications In the brick business, Sodium Carbonate is used as a wetting agent to minimize the quantity of water required to extrude clay. It is also used as a foaming agent and abrasive in toothpaste.

Conclusion

Sodium Carbonate Solution is corrosive and alkaline. Irritation might occur if the product comes into direct contact with the skin or eyes. Inhaling Sodium Carbonate dust or vapours can induce mucous membrane and airway irritation, as well as acute coughing and shortness of breath. High amounts might cause skin burns and eye irritation.