Question

Which of the following describes the relationship between acid strength and Ka value for weak acids?

A.When the Ka decreases, the acid strength increases.

B.When the Ka increases, the acid strength increases.

C.When the Ka increases, the acid strength decreases.

D.When the Ka increases, the acid strength is unchanged.

Answer 1

Acidic strength depends on Ka value. The more the Ka is, stronger the acid is.
Hence option B is correct.

Answer 2

Answer: Option (B) is the correct answer.

Explanation:

When more effectively an acid is able to dissociate completely and give a proton or
`H^(+)` ion then it is known as acid strength.

For example, HCl is a strong acid and thus completely dissociates to give proton.

`HCl \rightleftharpoons H^(+) + Cl^(-)`

Whereas
`K_(a)` is known as the acid dissociation constant. More is the value of
`K_(a)` more will be the acidic strength of acid.

Thus, we can conclude that when the
`K_(a)` increases, the acid strength increases best describes the relationship between acid strength and Ka value for weak acids.