Answer:
The correct option is H₂O is an acid and OH⁻ is its conjugate base.
Explanation:
According to the Bronsted-Lowry theory, an acid is a substance capable of yielding a hydrogen ion while a base is a species capable of accepting a hydrogen ion.
A conjugated acid-base pair is a pair of chemical species capable of transforming into each other by exchange of a proton. That is, a conjugated acid is the species that forms after the base accepts a proton. In contrast, a conjugate base is the species that forms after an acid donates its proton.
So, in this case water acts as an acid, yielding a proton to HCO₃⁻, which in turn acts as a base.
<u><em>The correct option is H₂O is an acid and OH⁻ is its conjugate base.</em></u>