Question

What is the difference between an acid and its conjugate base?
Question 1 options:
A.) The physical state of the acid changes.
B.) The acid donates an H + ion.
C.) The conjugate base accepts an OH– ion.
D.) The size of the ion always doubles

Answer 1

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

Answer 2

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.