Final answer:
The reactants in the given chemical equation H₂ + O₂ → CO₂ + H₂O are H₂ and O₂.
Step-by-step explanation:
The reactants in the chemical equation H₂ + O₂ → CO₂ + H₂O are H₂ and O₂. These are the substances that are combined to form the products CO₂ and H₂O. Reactants are the starting materials in a chemical reaction, and in this case, hydrogen gas (H₂) and oxygen gas (O₂) are the reactants.
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