SULPHURLECTURE

SULPHUR (S)

1. Introduction

Sulphur is a non-metal found in Group 16 (VI A) of the periodic table. Atomic number: 16 Symbol: S Electronic configuration: 2, 8, 6

2. Electronic Structure of Sulphur

Sulphur has 16 electrons arranged as:

1s² 2s² 2p⁶ 3s² 3p⁴

Diagram: Electronic arrangement of Sulphur (2,8,6)

3. Physical Properties of Sulphur

• Yellow crystalline solid
• Brittle and non-metallic
• Insoluble in water
• Soluble in carbon disulphide
• Low melting point

4. Chemical Properties of Sulphur

1. Reaction with Oxygen

S + O₂ → SO₂

2. Reaction with Metals

Fe + S → FeS

3. Reaction with Hydrogen

H₂ + S → H₂S

4. Reaction with Concentrated Acids

Acts as reducing agent.

5. Allotropes of Sulphur

• Rhombic sulphur (α-sulphur)
• Monoclinic sulphur (β-sulphur)
• Plastic sulphur

Diagram: Different allotropes of Sulphur

6. Uses of Sulphur

• Manufacture of tetraoxosulphate (VI) acid
• Vulcanization of rubber
• Manufacture of matches and gunpowder
• Production of fungicides and insecticides

7. Compounds of Sulphur

Compound	Formula	Property
Sulphur dioxide	SO₂	Acidic gas
Sulphur trioxide	SO₃	Reacts with water to form acid
Hydrogen sulphide	H₂S	Rotten egg smell
Tetraoxosulphate (VI) acid	H₂SO₄	Strong acid

8. Industrial Preparation of Tetraoxosulphate (VI) Acid (H₂SO₄)

Prepared by the Contact Process.

Step 1: Burning Sulphur

S + O₂ → SO₂

Step 2: Oxidation

2SO₂ + O₂ ⇌ 2SO₃ (Vanadium(V) oxide catalyst)

Step 3: Absorption

SO₃ + H₂SO₄ → H₂S₂O₇

H₂S₂O₇ + H₂O → 2H₂SO₄

Diagram: Contact Process for H₂SO₄ Production

9. Uses of Tetraoxosulphate (VI) Acid

• Manufacture of fertilizers
• Petroleum refining
• Car batteries (lead-acid batteries)
• Manufacture of detergents and explosives
• Drying agent in laboratory

END OF LECTURE