If an acetic acid,HC₂H₃O₂,buffer solution contains [HC₂H₃O₂] = 0.12 M and [C₂H₃O₂^-] = 0.15 M,what is the [H₃O⁺] in the solution? HC₂H₃O₂ (aq)+ H₂O (l)$\leftrightarrow$ H₃O⁺ (aq)+ C₂H₃O₂^- (aq)K = 1.8 × 10^-⁵

Question

Quizplus · Accepted Answer

The concentration of $[H_3O^+]$ can be calculated using the Henderson-Hasselbalch equation: $$pH = pKa + \log\left(\frac{[A^-]}{[HA]}\right)$$ Given that $K_a = 1.8 \times 10^{-5}$, $pKa = -\log(1.8 \times 10^{-5})$, $[A^-] = [CH_3COO^-] = 0.15\,M$, and $[HA] = [CH_3COOH] = 0.12\,M$, we can find the pH and then calculate $[H_3O^+]$ as $10^{-pH}$. The calculation aligns closest with the value given in choice A, $1.4 \times 10^{-5} M$, indicating the concentration of hydronium ions in the solution.

If an Acetic Acid,HC2H3O2,buffer Solution Contains [HC2H3O2] = 0 ↔\leftrightarrow↔ H3O+ (Aq)+ C2H3O2- (Aq)K = 1

If an Acetic Acid,HC₂H₃O₂,buffer Solution Contains [HC₂H₃O₂] = 0 $\leftrightarrow$ H₃O⁺ (Aq)+ C₂H₃O₂^- (Aq)K = 1