The pH of 1 N aqueous solutions of HCl, CH3COOH and HCOOH follows the order

Question

The pH of 1 N aqueous solutions of HCl, CH3COOH and HCOOH follows the order (A) HCl > HCOOH > CH3 COOH (B) HCl = HCOOH > CH3 COOH (C) CH3 COOH > HCOOH > HCl (D) CH3 COOH = HCOOH > HCl

Tardigrade Admin · Accepted Answer

According to Bronsted-Lowry concept of acids and bases, more is the stability of the conjugate base stronger will be the acid. The conjugate bases of the given solutions are :

H Cl ⇌ H^{+} + Conjugate base C I^{-}

H COO H ⇌ Conjugate base H CO O^{-} + H^{+}

H C_{3} COO H ⇌ Conjugate base C H_{3} CO O^{-} + H^{-}

Stability of conjugate base follows the order

Thus, the acidic strength follows the same order, i.e.

H Cl > H COO H > C H_{3} COO H

We also know that

p H

is inversely proportional to the concentration of

H^{+}

ions (acidic strength)
i.e

p H \propto \frac{1}{[ H ^{+} ]}

Thus, the pH of

1 N

aqueous solution follows the order

C H_{3} COO H > H COO H > H C I

Q. The $p H$ of $1 N$ aqueous solutions of $H Cl, C H_{3} COO H$ and $H COO H$ follows the order

$H Cl > H COO H > C H_{3} COO H$

$H Cl = H COO H > C H_{3} COO H$

$C H_{3} COO H > H COO H > H Cl$

$C H_{3} COO H = H COO H > H Cl$

Q. The pH of 1N aqueous solutions of HCl,CH3​COOH and HCOOH follows the order

HCl>HCOOH>CH3​COOH

HCl=HCOOH>CH3​COOH

CH3​COOH>HCOOH>HCl

CH3​COOH=HCOOH>HCl

Q. The $p H$ of $1 N$ aqueous solutions of $H Cl, C H_{3} COO H$ and $H COO H$ follows the order

$H Cl > H COO H > C H_{3} COO H$

$H Cl = H COO H > C H_{3} COO H$

$C H_{3} COO H > H COO H > H Cl$

$C H_{3} COO H = H COO H > H Cl$