When an acid donates a proton, what is its new classification?

When an acid donates a proton (H+), it transforms into its conjugate base. This process is rooted in the Bronsted-Lowry theory of acids and bases, which defines acids as proton donors and bases as proton acceptors. Therefore, when the acid donates a proton, it loses that positively charged hydrogen ion, resulting in a new species that has gained the ability to accept a proton in the future. This shift in identity is what leads to the classification of the substance as a base.

The idea of acidity and basicity is dynamic; thus, once the acid donates its proton, it no longer retains its original acidic characteristics and instead adopts those of a base, which is essential for understanding chemical reactions involving acids and bases.