Final answer:
A balanced chemical reaction has the same number of atoms for each element on both sides. The reaction 2H₂ + O₂ → 2H₂O is an example of such a balanced equation. Balancing chemical equations is crucial to reflect the conservation of matter.
Step-by-step explanation:
An example of a balanced chemical reaction is 2H₂ + O₂ → 2H₂O, where the number of atoms of each element is equal on both sides of the equation, respecting the law of conservation of mass. To balance a chemical equation, one must ensure that the quantities of each type of atom are equal on the reactant side and the product side. For instance, Mg + O₂ → MgO is balanced by writing 2Mg + O₂ → 2MgO.
Some other examples that require balancing include:
- Ca + H₂O → Ca(OH)₂ + H₂ becoming 2Ca + 2H₂O → 2Ca(OH)₂ + H₂
- CuCO₃ + H₂SO₄ → CuSO₄ + H₂O + CO₂ becoming CuCO₃ + H₂SO₄ → CuSO₄ + 2H₂O + CO₂
- CaCl₂ + Na₂CO₃ → CaCO₃ + 2NaCl