All About Baking Soda: Chemical Formula, Preparation, and Uses

Provided in this article is some information about various aspects of baking soda, which is a popular household ingredient used for various purposes.

Baking soda has numerous applications, and is primarily used in cooking purposes. It chemically known as sodium bicarbonate, or more precisely, by its IUPAC name, it is known as sodium hydrogen carbonate. It is represented by the chemical formula, NaHCO₃. So ‘what is baking soda’? Well, baking soda is in essence, a white crystalline salt of sodium, and it usually appears in a powder form.

Chemical Formula

Baking soda or baking powder has various chemical names like sodium bicarbonate (Na₂CO₃), bicarbonate of soda, sodium hydrogen carbonate ( NaHCO₃), etc. It is also called sodium bicarb or simply bicarb. Its main chemical formula is NaHCO₃, and it’s prepared industrially by Solvay process.

In this process, chemicals like calcium carbonate (CaCO₃), sodium chloride (NaCl), ammonia (NH₃), carbon dioxide (CO₂), and water (H₂O) are used. They react in various steps to give out the main product. The reactions proceeds in two steps:

Step 1: Reaction of aqueous solution of sodium hydroxide (NaOH) and carbon dioxide (CO₂) –

 CO₂ + 2 NaOH → Na₂CO₃ + H₂O

Step 2: Addition of more carbon dioxide to the above reaction –

Na₂CO₃ + CO₂ + H₂O → 2NaHCO₃

Chemical Reaction of Baking Soda in Water

NaHCO₃ consists of two ions, sodium ions (cations) Na⁺ and bicarbonate ions (anions) HCO₃^–. Explained below is the way of sodium bicarbonate getting dissolved in water by breaking into two ions.

NaHCO₃ → Na⁺(aq) + HCO₃^–(aq)

Thermal Decomposition of Baking Soda

The chemical formula for any compound gives us a broad insight about various chemical reactions and properties of that compound. It is clear that if we decompose the compound using heat energy, we can get compounds by the help of which it has been prepared. Represented below is the reaction of this process at 70° C.

2 NaHCO₃ → Na₂CO₃ + H₂O + CO₂

As a thumb rule, one can remember that most of the hydroxides in general, follow the above decomposition reactions. If heated further, at around 100° C, hydroxides breaks down into their corresponding oxides.

Na₂CO₃ → Na₂O (sodium oxide) + CO₂

Uses

Baking soda finds extensive use in industrial and household products. Sodium bicarbonate is used as a medicine for indigestion and acidic gas, by mixing in appropriate amounts in different medications. In renal and uric acid cases, sodium bicarbonate is used for treatment of urine related problems. A solution of sodium bicarbonate is considered to be intravenous in cases of acidosis. Sodium bicarbonate in proper amounts is added along with appropriate concentration of hydrogen peroxide solution, and serves as an alternative for toothpastes.

The most common use of baking soda in our households is for cleaning and bleaching purposes. Sodium bicarbonate is extensively used for baking purposes. It is also used as chemical leavening agents that helps the batter to rise when baked. However, adding too much of this powder to the batter leads to bitter taste, and hence, one must be careful about the appropriate amount of baking powder that has to be used.

Making a light paste of baking soda and water, and then applying them to skin area that has been affected by acne helps to relieve the acne within 2 – 3 days. All you have to do is to apply the paste continuously, and leave it to dry for 10 – 20 minutes. Various chemical and physical properties of baking soda can be figured out by understanding its formula, which contain elements and metals with distinct properties.