Question

Select the equations that are correctly balanced. caco 3 → cao co 2 fe 2o 3 3h 2 → 2fe 3h 2o al 3br 2 → albr 3 h 2o 2o 2 → h 2o 2

Answer 1

A balanced chemical equation has the same number of each element's atoms on both sides, reflecting the law of conservation of matter. In this case, only one of the student's provided equations is balanced (CuCO3 + H2SO4 → CuSO4 + H2O + CO2), while the others require adjustment to achieve balance.

Step-by-step explanation:

To determine if the chemical equations are balanced, we should count the atoms of each element on both the reactant and product sides.

1. Mg + O₂ → MgO Unbalanced: To balance, we need 2 Mg + O₂ → 2 MgO.
2. Ca + H₂O → Ca(OH)2 + H₂ Unbalanced: Correctly balanced, it's Ca + 2 H₂O → Ca(OH)₂ + H₂.
3. CuCO3 + H₂SO4 → CuSO4 + H₂O + CO₂ Balanced: Each element has the same number of atoms on both sides.
4. CaCl₂ + Na₂CO3 → CaCO3 + NaCl Unbalanced: To balance, we need CaCl₂ + Na₂CO3 → CaCO3 + 2 NaCl.
5. C₁₂H₂₂O₁₁ + O₂ → H₂O + CO₂ is Unbalanced: A complex balancing is needed due to the large number of carbon and hydrogen atoms.
6. BaCl₂ + H₂SO₄ → BaSO₄ + HCl Unbalanced: The balanced equation is BaCl₂ + H₂SO₄ → BaSO₄ + 2 HCl.