The ionisation constant of an acid, K_a is the measure of strength of an acid. The K_a values of acetic acid, hypochlorous acid and formic acid are 1.74 x 10^-5, 3.0 x 10^{- 8} and 1.8 x 10^{- 4}, respectively. Which of the following orders of pH of 0.1 mol dm^{- 3} solutions of these acids is correct?

see full answer

High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET

🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.

An Intiative by Sri Chaitanya

Acetic acid > hypochlorous acid > formic acid

Hypochlorous acid > acetic acid > formic acid

Formic acid > hlpochlorous acid > acetic acid

Formic acid > acetic acid > hypochlorous acid

answer is D.

(Unlock A.I Detailed Solution for FREE)

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

More is the acidic character, more is the value of K_a. High acidic character of acid have low value of pH.

Ka value is smallest for formic acid and highest for hypochlorous acid. Therefore, the correct order of the given acids:

$Hypochlorous acid < Acetic acid < Formic acid$

Watch 3-min video & get full concept clarity

No courses found

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test