Sulfur Dioxide Chemical Formula

Introduction to Sulphur dioxide:

The chemical formula of sulphur dioxide is SO₂. Molar mass of sulphur dioxide is 64.07g. Sulphur dioxide is a colorless gas with irritating and suffocating smell. Its meting and boiling point are -75.5˚ and -10˚C. Sulphur dioxide can be produced by some industrial processes and also by volcanoes.  Coal and some petroleum contain sulphur, so the combustion of coal and petroleum produces sulphur dioxide. The oxidation of sulphur dioxide can be carried out in presence of catalyst like NO₂ which forms H₂SO₄ that leads to acid rain.
The molecular formulas of the sulphur dioxide is as shown below,

Preparation of Sulphur Dioxide:

Sulphur dioxide can be prepared in many differnt methods; few of them are as follows

• It is prepared by burning sulphur in atmosphere.

S₈ + 8 O₂ ===> 8 SO₂

• It is also prepared by burning or roasting iron pyrites in air.

4 FeS₂ + 11 O₂ ===> 2 Fe₂O₃ + 8 SO₂.

• It is prepared in laboratory by heating copper turnings with concentrated H₂SO₄

Cu + 2H₂SO₄ ===> CuSO₄ + SO₂ + 2H₂O.
Reactions of sulphur dioxide:

• Sulphur dioxide reacts with alkali solutions to give sulphites.

SO₂ + 2 NaOH ===> Na₂SO₃ + H₂O

• Sulphur dioxide reacts with halogens and gives sulphuryl chloride.

SO₂ + Cl₂ ===> SO₂Cl₂.

• Hydrogen sulphide reduces sulphur dioxide and gives sulphur element.

SO₂ + 2 H₂S ===> 3 S + 2 H₂O.

Structure and Bonding in Sulphur Dioxide:

Sulphur dioxide is a bent shaped molecule with O-S-O bond angle 119˚ and the bond length of S-O is 143.1 pm. The sulphur atom is sp² hybridized. The oxidation state of sulphur is +4.
The possible resonance structures of Sulphur dioxide SO₂.

Uses of Sulphur dioxide (SO₂):

• Sulphur dioxide is used in the production of sulphuric acid.
• It is used as a preservative for dried fruits and apricots.
• It is used as a reducing agent and refrigerant
• It is also used as a solvent for some reactions.
• It is used in making wine.

Safety Measures:

Inhaling of sulphur dioxide causes some respiratory diseases and symptoms, which leads to difficulty in breathing and premature death. It also changes lung’s defences and causes some cardiovascular diseases. People who are suffering from asthma, lung or heart disease are much sensitive to sulphur dioxide. Sulphur dioxide not only affects human being but also it damages trees and crops along with oxides of nitrogen.  And, also causes the formation of microscopic aerosols of acid which have serious health implications.