The pKa of acetic acid is 4.76. Which of the following is the pKa of hydrochloric acid?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → −7
NCERT (2026-27 edition):
8.9.1 Reactions Involving Cleavage of O–H Bond – “For convenience, the strength of an acid is generally indicated by its pKa value rather than its Ka value. pKa = – log Ka The pKa of hydrochloric acid is –7.0, where as pKa of trifluoroacetic acid (the strongest carboxylic acid), benzoic acid and acetic acid are 0.23, 4.19 and 4.76, respectively.”