This is the net ionic equation for the neutralization of a hydrochloric acid with sodium hydroxide:
NaOH (aq) + HCl (aq) H2O (l) + NaCl (aq)
Na (aq) + Cl (aq) NaCl (aq)
OH (aq) + H+ (aq) → H2O (1)
NaOH (aq) + HCl (aq) → H2O (I) + NaCl (aq)
Na (aq) + H+(aq) → NaH (aq)
Question 3 (1 point)
This is the net ionic equation for the complete neutralization of a generic diprotic acid with sodium hydroxide:
H2A (aq) + 2 NaOH (aq) 2 H2O (I) + Na2A (aq)
OH (aq) + H+ (aq) → H2O (1)
2 Na (aq) + A2-(aq) → Na2Cl (s)
2 OH (aq) + 2 H* (aq) → 2H2O (1)
The Correct Answer and Explanation is :
Correct Net Ionic Equation:
For the complete neutralization of a generic diprotic acid (H₂A) with sodium hydroxide (NaOH), the correct net ionic equation is:
[
H_2A (aq) + 2 OH^- (aq) \rightarrow 2 H_2O (l) + A^{2-} (aq)
]
Explanation (300 Words):
A diprotic acid is an acid that can donate two protons (H⁺) per molecule. The general formula for a diprotic acid is H₂A, where “A” represents the conjugate base after losing both protons. Common examples of diprotic acids include sulfuric acid (H₂SO₄), carbonic acid (H₂CO₃), and oxalic acid (H₂C₂O₄).
When a diprotic acid reacts with sodium hydroxide (NaOH), a strong base, neutralization occurs in two steps:
- First Proton Donation:
[
H_2A (aq) + OH^- (aq) \rightarrow H_2O (l) + HA^- (aq)
]
The first hydroxide ion removes one proton from H₂A, forming the intermediate conjugate base HA⁻. - Second Proton Donation:
[
HA^- (aq) + OH^- (aq) \rightarrow H_2O (l) + A^{2-} (aq)
]
The second hydroxide ion removes another proton from HA⁻, leaving the final conjugate base A²⁻.
Since sodium hydroxide fully dissociates in water, Na⁺ ions are spectator ions and do not participate in the actual reaction. The final net ionic equation simplifies to:
[
H_2A (aq) + 2 OH^- (aq) \rightarrow 2 H_2O (l) + A^{2-} (aq)
]
This equation represents the neutralization process for any diprotic acid reacting with a strong base. The reaction is essential in titration calculations, buffer solutions, and various industrial applications like wastewater treatment and pharmaceutical formulations.