What is S2? Important knowledge about S2

In this lecture, we will learn about Sulfur – represented by the chemical symbol S₂.

1. Definition:
   Sulfur, also known as Sulphur in English, is a chemical element belonging to the chalcogen group in the periodic table. It has an atomic mass of 32.06 and is represented by the symbol S₂. Sulfur molecules usually appear as S₈ compounds, which means there are 8 sulfur atoms linked together. S₂ does not form ions under natural conditions.

2. Characteristics:
   2.1 Physical properties: Sulfur appears as a solid, yellow, odorless substance with no pH level (since it doesn’t dissolve in water).
   2.2 Chemical properties: Sulfur is capable of reacting with a variety of other substances, such as metals, acids, and non-metals, to form new compounds.

3. Chemical equations:
   Common chemical equations of Sulfur include reactions with metals (like Fe, Cu, Zn), acids (like HCl, H₂SO₄), non-metals (like O₂, H₂) and salts (like NaCl, KCl).
   For example:

   • S + Fe -> FeS
   • S + HCl -> H₂S + Cl₂
   • S + O₂ -> SO₂
   • S + H₂ -> H₂S
   • S + NaCl -> Na₂S + Cl₂

4. Sulfur preparation:
   4.1 In the laboratory, Sulfur can be prepared through the reaction between H₂S and O₂.
   Example: 2H₂S + 3O₂ -> 2SO₂ + 2H₂O
   4.2 Industrially, Sulfur is often obtained from natural gas and petroleum containing H₂S. The process typically includes separating H₂S from the gas stream then burning H₂S to obtain Sulfur.