Introduction to Balancing Chemical Equations

Key Concepts

Balancing Equations: Ensures the same number of each type of atom on both sides of the equation.
Unbalanced vs. Balanced Equations:
- Unbalanced Equation: Different number of atoms on each side.
- Balanced Equation: Same number of each type of atom on both sides.

Word Equation: Hydrogen gas + Chlorine gas → Hydrochloric acid
Chemical Equation: ( H_2 + Cl_2 \rightarrow HCl )
- Unbalanced State:
  - 2 Hydrogen atoms on reactant side, 1 on product side.
  - 2 Chlorine atoms on reactant side, 1 on product side.
- Balancing Process:
  - Add 2 HCl on the product side to balance the equation.
  - Balanced Equation: ( H_2 + Cl_2 \rightarrow 2HCl )

Word Equation: Hydrogen gas + Oxygen gas → Water
Chemical Equation: ( H_2 + O_2 \rightarrow H_2O )
- Unbalanced State:
  - Hydrogens balance (2 on each side).
  - Oxygen unbalanced (2 on reactant side, 1 on product).
- Balancing Process:
  - Add another ( H_2O ) molecule on product side.
  - Adjust hydrogens by adding ( H_2 ), to balance.
  - Balanced Equation: ( 2H_2 + O_2 \rightarrow 2H_2O )

Subscripts: Should not be changed when balancing equations.
- Changing subscripts alters the substance's identity (e.g., water ( H_2O ) to hydrogen peroxide ( H_2O_2 )).
Coefficients: Numbers placed in front to balance the equations.

Visual Representation: Helps to understand the balancing process visually with atoms.
Use of Charts:
- List atoms and their quantities on each side of the equation.
- Adjust coefficients to balance the atoms.
- Example shown using nitrogen and hydrogen:
  - Start with ( N_2 + H_2 \rightarrow NH_3 )
  - Balancing Process:
    - Balance Nitrogens: ( 2NH_3 ), Nitrogens balanced.
    - Balance Hydrogens: Add coefficient 3 to ( H_2 ).
  - Balanced Equation: ( N_2 + 3H_2 \rightarrow 2NH_3 )