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Aldehydes, Ketones, and Carboxylic Acids — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryAldehydes, Ketones, and Carboxylic Acids1 Mark
MCQ
Which of the following is the strongest acid?
  • ✓
    $\text{HCOOH (pKa​=3.77)}$
  • B
    $\mathrm{C}_6 \mathrm{H}_5 \mathrm{COOH}(\mathrm{pKa}=4.22)$
  • C
    $\mathrm{CH}_3 \mathrm{COOH}(\mathrm{pKa}=4.71)$
  • D
    $\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{COOH}(\mathrm{pKa}=4.88)$
✓

Answer

Correct option: A.
$\text{HCOOH (pKa​=3.77)}$
Lower the $pKa$ value, higher is the acid dissociation constant and so, higher is the acidic strength.
Hence, option a with least $pKa$​ value is the correct answer.

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