Which ion is referred to as bisulfate?

The ion referred to as bisulfate is HSO4-. This ion is derived from sulfuric acid (H2SO4) and occurs when one of its protons is removed, resulting in the bisulfate anion. Bisulfate plays an important role in various chemical reactions, including those in biological systems, and is involved in the maintenance of pH levels in cells and tissues.

The naming convention includes "bisulfate" to indicate that it has one hydrogen atom still associated with the sulfate ion (SO4 2-), distinguishing it from the fully deprotonated sulfate ion. This is a common practice in chemistry to provide clarity on the protonation state of the ion.