Home
Class 12
CHEMISTRY
A weak monobasic acid is half neutralize...

A weak monobasic acid is half neutralized by a strong base. If the Ph of the solution is 5.4 its `pK_(a)` is

A

6.8

B

2.7

C

5.4

D

10.8

Text Solution

Verified by Experts

The correct Answer is:
C
After half neutralization
`(["sal t"])/(["Acid"])= (1//2)/(1//2)=1/1`
`pH=pK_(a) + "log"(["sa lt"]) /(["Acid"]) =pK_(a) impliespK_(a)=5.4`
Promotional Banner

Similar Questions

Explore conceptually related problems

The pH of a weak mono acidic base, neutralized upto 80% with a strong acid in a dilute solution, is 7.40. The ionization constant of the base is

Which of the following statement (s) is (are) correct ? (1) . The pH of 1.0 xx 10^(-8) M solution of HCI is 8 (2). The conjugate base of H_(2)PO_(4)^(-) " is " HPO_(4)^(2-) (3). Autoprotolysis constant of water increases with temperature (4). When a solution of a weak monoprotic acid is titrated against a strong base at half neutralization point pH = (1//2) pK_(a)

Assertion : In a titration of weak monoprotic acid with strong base, the pH at the half equivalent point is pK_(a) . Reason : At half equivalence point, it will form acidic buffer at its maximum capacity where [acid] = [salt].

pH of a salt of a strong base with weak acid

20 mL of a weak monobasic acid (HA) requires 20 mL 0.2 M NaOH for complete titration. If pH of solution upon addition of 10 mL of this alkali to 25mL of the above solution of HA is 5.8 . The pK_(a) of the weak acid is