Key Topics Covered:

1. Law of Conservation of Mass

   • The mass of reactants is always equal to the mass of products. This principle requires that chemical equations must be balanced.

2. Balancing Simple Equations

   • Step-by-step guide to balancing equations:
     1. Identify the reactants and products.
     2. Count the number of atoms of each element on both sides.
     3. Adjust coefficients to balance atoms.
   • Example: H2+O2→H2OH_2 + O_2 rightarrow H_2OH2​+O2​→H2​O Balanced: 2H2+O2→2H2O2H_2 + O_2 rightarrow 2H_2O2H2​+O2​→2H2​O

3. Balancing Complex Equations

   • Balancing more challenging reactions, ensuring atoms of each element are balanced in reactions involving polyatomic ions or multiple elements.

4. Tips for Balancing Equations

   • Start with balancing elements that appear in only one reactant and one product.
   • Balance hydrogen and oxygen last.