2SO₂ + O₂ → 2SO₃
Sulfur (S):
* Reactants: 2SO₂ contains 2 * 1 = 2 sulfur atoms
* Products: 2SO₃ contains 2 * 1 = 2 sulfur atoms
Oxygen (O):
* Reactants: 2SO₂ contains 2 * 2 = 4 oxygen atoms
* O₂ contains 2 oxygen atoms
* Total reactants: 4 + 2 = 6 oxygen atoms
* Products: 2SO₃ contains 2 * 3 = 6 oxygen atoms
Therefore:
* There are 2 sulfur atoms on both sides of the equation.
* There are 6 oxygen atoms on both sides of the equation.
Key Point: A balanced chemical equation ensures that the number of atoms of each element is the same on both the reactant and product sides. This follows the law of conservation of mass.
