Sulphuric acid and Sulphurous acid are two such compounds which are acids. The main difference between sulphuric acid and sulphurous acid is that sulphuric acid has the chemical formula H2so4 and is a good oxidizing agent whereas sulphurous acid hasthe chemical formula H2SO3 and is a good reducing agent.

**Sulphuric Acid:**

Sulphuric acid, also known as sulfuric acid, is a strong and highly corrosive acid with the chemical formula H2SO4. It is one of the most commonly used industrial chemicals, with a wide range of applications in various industries such as manufacturing, mining, and agriculture.

**Properties of Sulphuric Acid:**

1. Chemical Formula: H2SO4
2. Molecular Weight: 98.08 g/mol
3. Physical State: Colorless to slightly yellow viscous liquid
4. Odor: Odorless
5. Density: 1.84 g/mL
6. Melting Point: 10.3°C
7. Boiling Point: 337°C
8. Solubility: Miscible with water, exothermic reaction

**Production of Sulphuric Acid:**

Sulphuric acid is primarily produced through the contact process, which involves several steps:

1. Sulphur is burned to produce sulfur dioxide (SO2).
2. The produced SO2 is then oxidized to form sulfur trioxide (SO3) using a catalyst such as vanadium pentoxide (V2O5).
3. The SO3 is dissolved in concentrated sulphuric acid to form oleum.
4. Finally, the oleum is diluted with water to produce sulphuric acid.

**Uses of Sulphuric Acid:**

Sulphuric acid is widely used in various industries due to its strong acidic properties. Some common applications include:

1. Manufacturing of fertilizers: Sulphuric acid is a key component in the production of phosphate fertilizers like ammonium phosphate and superphosphate.
2. Chemical manufacturing: It is used in the production of various chemicals such as dyes, pigments, detergents, and pharmaceuticals.
3. Petroleum refining: Sulphuric acid is used in the refining process to remove impurities from crude oil and gasoline.
4. Metal processing: It is used for pickling and etching metals, as well as in the production of batteries and lead-acid accumulators.
5. Water treatment: Sulphuric acid is added to water to adjust pH levels and remove impurities.

**Sulphurous Acid:**

Sulphurous acid, also known as sulfur dioxide, is a weak acid with the chemical formula H2SO3. It is a colorless gas with a pungent odor and is typically produced by burning sulfur or by the combustion of fossil fuels containing sulfur compounds.

**Properties of Sulphurous Acid:**

1. Chemical Formula: H2SO3
2. Molecular Weight: 82.07 g/mol
3. Physical State: Colorless gas
4. Odor: Pungent
5. Density: 2.927 g/L (gas)
6. Melting Point: -75°C
7. Boiling Point: -10°C
8. Solubility: Soluble in water, forming sulfurous acid

**Formation of Sulphurous Acid:**

Sulphurous acid is formed when sulfur dioxide (SO2) dissolves in water. The reaction occurs as follows:

SO2 + H2O ⇌ H2SO3

**Uses of Sulphurous Acid:**

Sulphurous acid has limited applications due to its volatility and instability. Some of its uses