Chemical Equation Balancer

What Is a Chemical Equation?

A chemical equation represents a reaction using chemical formulas. Reactants appear on the left and products on the right, separated by an arrow (→). Balancing ensures the law of conservation of mass is met: the number of atoms of each element is the same on both sides.

How to Balance (At a Glance)

1. Write the unbalanced equation (formulas correct).
2. Count atoms of each element on both sides.
3. Add coefficients (whole numbers) to species to equalize counts.
4. Balance elements that appear in fewer species first (often metals, then non‑metals, then H and O).
5. Reduce coefficients to the smallest whole‑number ratio and double‑check counts.

Common Reaction Types

• Combustion: Hydrocarbon + O₂ → CO₂ + H₂O
• Acid–Base: Acid + Base → Salt + Water
• Redox: Electron transfer changes oxidation states (balance via half‑reactions)
• Synthesis/Decomposition: A + B → AB, or AB → A + B

Worked Examples

More Examples

Redox Primer (Acidic/Basic)

Redox (reduction–oxidation) reactions involve electron transfer. Balancing typically uses the half‑reaction method:

1. Split into oxidation and reduction half‑reactions; assign oxidation states.
2. Balance atoms other than O and H.
3. Balance O with H₂O and H with H⁺ (acidic) or OH⁻ (basic).
4. Balance charge with electrons (e⁻).
5. Equalize electrons and add half‑reactions; simplify.