Which of the following acids has the highest pKa value?
Correct answer: A. HClO₃
- A. HClO₃
- B. HNO₃
- C. H₂SO₄
- D. HClO₄
Explanation
The highest pKa value corresponds to the weakest acid. Among the given options, nitric acid, sulfuric acid, and perchloric acid are all very strong acids with highly negative pKa values. Chloric acid (HClO₃) is also a strong acid, but it is the weakest among this group, meaning it has the largest (least negative) pKa value
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About Acids, Bases and Salts
Acid and base behaviour is explained through the Bronsted-Lowry transfer of protons and the Lewis donation or acceptance of electron pairs. The topic includes pH, pOH, ionisation and water equilibrium, plus salt formation and hydrolysis, where a salt solution may become acidic, basic or neutral.
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