Question

What is the difference between an acid and its conjugate base?

Answer 1

Answer : The correct option is B: The acid donates an H + ion.

Explanation :

According to Bronsted -Lowry theory, an acid is a substance that donates a proton. The substance that is left after the proton is donated is known as "conjugate base" of that acid.

Consider a general acid HA. The dissociation reaction of the acid can be written as follows.

$HA (aq) + H_{2}O (l)\rightleftharpoons H_{3}O^{+} (aq)+ A^{-}(aq)$

In the above example, HA behaves as an acid because it donates proton to H₂O. When the proton is donated, A⁻is formed on the product side which is a conjugate base of HA.

From above discussion, we can say that a substance and its conjugate differ by a proton, H⁺ only.

Therefore the acid donates an H + ion is the correct option.

Answer 2

I took a quiz with this question on it, the answer is
 B) The acid donates an H + ion