Balance the complete ionic equation when aqueous barium hydroxide reacts with aqucous hydrochloric acid
The Correct Answer and Explanation is:
Correct Answer:
The balanced complete ionic equation is:
Ba²⁺(aq) + 2OH⁻(aq) + 2H⁺(aq) + 2Cl⁻(aq) → Ba²⁺(aq) + 2Cl⁻(aq) + 2H₂O(l)
Explanation:
When aqueous barium hydroxide reacts with aqueous hydrochloric acid, a neutralization reaction occurs. Barium hydroxide, Ba(OH)₂, is a strong base that completely dissociates in water into barium ions (Ba²⁺) and hydroxide ions (OH⁻). Similarly, hydrochloric acid, HCl, is a strong acid that completely dissociates into hydrogen ions (H⁺) and chloride ions (Cl⁻).
Step 1: Write the dissociation of the reactants
- Ba(OH)₂(aq) → Ba²⁺(aq) + 2OH⁻(aq)
- 2HCl(aq) → 2H⁺(aq) + 2Cl⁻(aq)
Step 2: Combine the ions to form the complete ionic equation
- Ba²⁺(aq) + 2OH⁻(aq) + 2H⁺(aq) + 2Cl⁻(aq)
Step 3: Determine the products
In an acid-base reaction, the hydroxide ions (OH⁻) from the base react with the hydrogen ions (H⁺) from the acid to form water:
- 2OH⁻(aq) + 2H⁺(aq) → 2H₂O(l)
The chloride ions (Cl⁻) and barium ions (Ba²⁺) remain in the solution as spectator ions. So, the products are:
- Ba²⁺(aq) + 2Cl⁻(aq) + 2H₂O(l)
Step 4: Combine everything into the full balanced complete ionic equation:
Ba²⁺(aq) + 2OH⁻(aq) + 2H⁺(aq) + 2Cl⁻(aq) → Ba²⁺(aq) + 2Cl⁻(aq) + 2H₂O(l)
This equation is balanced because the number and type of atoms, as well as the total charge, are the same on both sides. Note that the barium and chloride ions are spectator ions because they do not participate directly in the formation of the water.
