Chemical Reactions and Equations Cheat Sheet

Key Definitions

• Chemical Reaction: A process where reactants transform into products. ✅

• Reactants: Substances that undergo change in a reaction. ✅

• Products: Substances formed as a result of a reaction. ✅

• Balanced Equation: An equation with equal numbers of each type of atom on both sides. ✅

Important Concepts

Types of Reactions

• Combination Reaction: Two or more substances combine to form one product.

• Decomposition Reaction: A single compound breaks down into two or more products.

• Displacement Reaction: An element displaces another in a compound.

• Redox Reaction: Involves transfer of electrons, oxidation and reduction occur simultaneously.

Balancing Equations

• Ensure the number of atoms of each element is the same on both sides.

• Use coefficients to balance, not subscripts.

Key Formulas

• A, B: Reactants

• C, D: Products

• a, b, c, d: Coefficients (moles of each substance)

Common Mistakes to Avoid

Common Mistake: Forgetting to balance the equation; always check atom counts on both sides.

Memory Tricks

Tip: "LEO says GER" — Loss of Electrons is Oxidation; Gain of Electrons is Reduction.

Key Diagrams

Combination: A + B → AB
Decomposition: AB → A + B
Displacement: A + BC → AC + B
Redox: 2Mg + O2 → 2MgO (Oxidation: Mg, Reduction: O)