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[cite_start]<div style="margin-top: 1px; margin-bottom: 20px; border: 1px solid #ddd; border-radius: 5px; overflow: hidden; box-sizing: border-box;"><div style="background: #f5f5f5; padding: 10px 15px; border-bottom: 1px solid #ddd;"><h4 style="margin: 0; font-size: 13pt; text-decoration: underline;"><span style="color: #0000ff; font-weight: bold;">Question 38</span></h4></div><div style="padding: 15px; background: #fff; line-height: 1.55; font-family: Georgia, Palatino, serif; font-size: 12pt;"><div style="margin: 8px 0;">The Lewis electron-dot diagrams of the \(HClO_{3}\) molecule and the \(HClO_{2}\) molecule are shown above at the left and right, respectively. [cite: 124, 125] [cite_start]Which of the following statements identifies the stronger acid and correctly identifies a factor that contributes to its being the stronger acid? [cite: 126, 127][cite_start]</div><div style="margin: 8px 0; padding-left: 20px; padding-right: 20px;">(A) \(HClO_{3}(aq)\) is the stronger acid because its molecules experience stronger London dispersion forces. [cite: 129][cite_start]<br />(B) \(HClO_{3}(aq)\) is the stronger acid because the additional electronegative oxygen atom on the chlorine atom stabilizes the conjugate base. [cite: 130][cite_start]<br />(C) \(HClO_{2}(aq)\) is the stronger acid because its molecules experience weaker London dispersion forces. [cite: 131][cite_start]<br />(D) \(HClO_{2}(aq)\) is the stronger acid because the lone pairs of electrons on the chlorine atom stabilize the conjugate base. [cite: 132]</div></div></div><div style="margin-top: 10px; border: 1px solid #ddd; border-radius: 5px; padding: 10px; background: #fff;"><details><summary style="color: #ff00ff; cursor: pointer; font-weight: bold; font-family: Georgia, Palatino, serif; font-size: 13pt;">▶️ Answer/Explanation</summary><div style="margin-top: 12px; padding: 10px; background: #f9f9f9; border-left: 3px solid #ccc; font-family: Georgia, Palatino, serif; font-size: 12pt; line-height: 1.65;"><div style="font-weight: bold; font-size: 1.1em;">Detailed solution</div><p><b>1. Identify the Stronger Acid:</b><br />For oxyacids with the same central atom (Cl), acid strength increases as the number of oxygen atoms increases. This is because oxygen is highly electronegative.<br />\(HClO_{4} > HClO_{3} > HClO_{2} > HClO\)<br />Therefore, \(HClO_{3}\) is the stronger acid. This eliminates options (C) and (D).<br /><br /><b>2. Analyze the Reason:</b><br />Acid strength is determined by the stability of the conjugate base formed after the proton (\(H^{+}\)) is donated.<br /><ul><li>\(HClO_{3}\) forms \(ClO_{3}^{-}\) (chlorate).</li><li>\(HClO_{2}\) forms \(ClO_{2}^{-}\) (chlorite).</li></ul><br /><b>3. Compare Conjugate Base Stability:</b><br />The \(ClO_{3}^{-}\) ion has three highly electronegative oxygen atoms that can pull electron density away from the central chlorine and delocalize the \(-1\) charge through resonance. The \(ClO_{2}^{-}\) ion only has two oxygen atoms to do this. <br /><br /><b>4. Conclusion:</b><br />The additional oxygen atom in \(ClO_{3}^{-}\) makes it more stable than \(ClO_{2}^{-}\) because the negative charge is "spread out" more effectively. A more stable conjugate base means the original acid (\(HClO_{3}\)) is stronger. [cite_start]Option (B) provides this correct reasoning. [cite: 130]<br />✅ <strong>Answer: (B)</strong></p></div></details></div>