Sulfurous Acid Formula

Sulfurous Acid Formula

Hydrogen, sulphur, and oxygen are the components of Sulfurous Acid Formula. The gas hydrogen is combustible, tasteless, colourless, and odourless. It has an atomic number of 1, and the letter H is used to denote it. An important non-metal found in Group 16 of the periodic table is sulphur. It has an atomic number of 16, and the letter S is used to denote it. It manifests as a crystalline, bright yellow solid at ambient temperature. An excellent oxidising agent and highly reactive nonmetal is oxygen. The periodic table’s Group 16 contains it. It has an atomic number of 8, and the letter O stands for it.

Sulfurous acid is a weak, colourless inorganic acid with a strong sulphurous aroma. H2SO3 is the chemical formula for sulfuric acid.

Both tissues and metals are corroded by it. H2SO3 is a hydrogen sulfite conjugate acid, a sulfur oxoacid, and a tautomer of sulfonic acid. Hydrogen thiosulfate, sulfur dioxide solution, and trioxosulfuric acid are among the alternate names for Sulfurous Acid Formula. It is a species at the transition between SO2 and acid rain (Sulfur dioxide).

Sulfurous Acid Chemical Formula

A chemical compound with the chemical formula H2SO3 is referred to as Sulfurous Acid Formula. Chemically, H2SO3 is referred to as sulfuric acid.

Trioxosulfuric acid, sulfur dioxide solution, and di-hydrogen trioxosulfate are other names for sulfurous acid. It is an intermediary species that use sulfur dioxide to produce acid rain (which is SO2).Trioxosulfuric acid is defined as a colorless liquid that is corrosive to tissue and metals and has a strong, burning sulfur odour. It is a sulfur oxoacid, a tautomer of sulfonic acid, and the conjugate acid of a hydrogen sulfite.

What is Sulfurous Acid?

Sulfurous acid, often known as sulphuric acid, is a chemical substance with the formula H2SO3. Although this molecule has been found in the gaseous phase, there is no proof that sulfuric acid is present in the solution.

However, common bisulfite (or hydrogen sulfite), anions, and sulfite are the conjugate bases of this elusive acid. Whereas, when sulfur dioxide dissolves in water, weak and unstable acid is created. Although the specific reason why sulfur dioxide compound truly exists in solutions is unknown, its molecules have been found in the gaseous state.

It functions as a bleaching and reducing agent.

The Sulfurous Acid Formula component is not isolated in its pure form because it only forms in the aqueous solution.

Structure of Sulfurous Acid

When students examine the chemical composition of acid, they can see that the sulphur atom, which is located in the center of the molecule, is joined to three oxygen atoms, two of which are joined by a single link and one by a double bond. One connection holds the two hydrogen atoms to the oxygen atoms together. The structural formula for sulfuric acid is typically stated as follows.

Preparation of Sulfurous Acid

These techniques can be used to make sulfuric acid:

The aqueous solution of sulfur dioxide is referred to as Sulfurous Acid Formula. Sulfur dioxide can therefore be created by mixing it with water. The reaction’s chemical equation can be written as,


The aforementioned reaction is, however, reversible, and the Sulfurous Acid Formula that is produced easily breaks down to release the reactants. So it is impossible to separate sulfuric acid in its acid state. It is created more frequently as sodium or potassium salts.

Properties of Sulfurous Acid  

Some physical and chemical properties of Sulfurous Acid Formula are mentioned below for students’ understanding. 

Physical Properties of Sulfurous Acid

  • The liquid form of sulfuric acid is colourless.

  • Sulfurous acid has a strong, unpleasant smell.

  • Sulfurous acid has a molecular weight of 82.07 g/mol.

  • It has an 81.97 g/mol monoisotopic mass.

  • Sulfurous acid reaches its boiling point at -60 °C.

  • Sulfurous acid has a density of 1.03 g/mL.

Chemical Properties of Sulfurous Acid

  • Since sulphurous acid is unstable, its pure form has never been isolated. Sulfur dioxide and water are formed when H2SO3 breaks down. The chemical process is described below:

H2SO3  ⇢  SO2+H2O

  • Sulfurous acid changes into sulfuric acid when exposed to air.

2H2SO3 + O2  ⇢  2H2SO4

Uses of Sulfurous Acid

  • The aqueous solution of sulphur dioxide, commonly known as sulphurous acid, is employed as a reducing agent and a disinfectant.

  • Chlorine-sensitive goods are bleached with sulfuric acid instead of chlorine.

  • Paper goods are produced using sulfuric acid.

Sample Questions

A few sample questions for students will be helpful to understand the concept and formulas of Chemistry. These, along with multiple quality educational resources can be accessed on the Extramarks website.

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Helium Gas Formula Net Ionic Formula
Partition Coefficient Formula Percarbonic Acid Formula
Potassium Acetate Formula Selenous Acid Formula
Potassium Nitrite Formula
FAQs (Frequently Asked Questions)

1. What kind of acid—strong or weak—is Sulfurous Acid Formula?

Sulfurous Acid Formula, in contrast to sulfuric acid, is a weak acid since it partially dissociates in water. When base-like water is present, the bisulfite ion is somewhat more effective in maintaining a proton.

2. Does Sulfurous Acid Formula pose a health risk?

Yes, Sulfurous Acid Formula is a hazardous substance. Burns may result from direct touch, and throat and neck irritation may result from inhalation. This substance releases caustic, noxious, and irritating fumes. It influences reproduction as well.