Write the balanced molecular equation for the neutralization reaction between HI and Ba(OH)2 in aqueous solution. Include physical states. Molecular equation: 2HI(aq) + Ba(OH)2(aq) → BaI2(aq) + 2H2O(l)
The Correct Answer and Explanation is:
Balanced Molecular Equation:
2HI(aq) + Ba(OH)₂(aq) → BaI₂(aq) + 2H₂O(l)
Explanation:
A neutralization reaction occurs when an acid reacts with a base to produce a salt and water. In this case, hydroiodic acid (HI), a strong acid, reacts with barium hydroxide (Ba(OH)₂), a strong base.
Hydroiodic acid (HI) exists in aqueous solution as hydrogen ions (H⁺) and iodide ions (I⁻). Barium hydroxide, being a strong base, dissociates completely in water to form barium ions (Ba²⁺) and hydroxide ions (OH⁻). The key process in the neutralization is the combination of hydrogen ions (H⁺) from the acid and hydroxide ions (OH⁻) from the base to form water molecules (H₂O).
Each molecule of barium hydroxide contains two hydroxide ions. Therefore, two molecules of hydroiodic acid are required to provide two hydrogen ions to fully neutralize one molecule of Ba(OH)₂. This leads to the balanced equation:
2HI(aq) + Ba(OH)₂(aq) → BaI₂(aq) + 2H₂O(l)
In this equation:
- Two moles of HI react with one mole of Ba(OH)₂.
- The salt formed is barium iodide (BaI₂), which remains dissolved in water as an aqueous solution.
- Two water molecules are formed as a result of the neutralization.
The physical states are important in understanding the nature of the substances involved. The reactants and the salt product are in aqueous form, indicating they are dissolved in water. The water formed appears as a liquid, denoted by (l).
This reaction exemplifies a typical strong acid–strong base reaction, leading to complete neutralization and the formation of a neutral salt solution.
