Lesson · S.3.3
Chemical reactions
Reactants, products, the main reaction types, and how to balance an equation so atoms are conserved, the way the TEAS presents them.
ObjectiveS.3.3Read2 minExam weightChemistry ≈ 18% of Science
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- Identify reactants and products in a chemical equation.
- Name a reaction as synthesis, decomposition, replacement, or combustion from its pattern.
- Balance a chemical equation by adjusting coefficients.
What the lesson concludes
- Reactants sit on the left of the arrow, products on the right.
- Conservation of mass means atom totals must match on both sides of a balanced equation.
- Synthesis combines, decomposition breaks apart, replacement reactions swap partners.
- Combustion reacts a substance with oxygen and releases heat.
- Balance by adjusting coefficients only, never the subscripts inside a formula.