The conjugate base of HSO4– is SO42-.
When HSO4– (hydrogen sulfate or bisulfate ion) donates a proton (H+), it forms SO42- (sulfate ion). This process is represented by the following chemical equation:
HSO4– → H+ + SO42-
In this reaction, HSO4– acts as an acid by donating a proton, and SO42- is its conjugate base. The concept of conjugate acids and bases is fundamental in understanding acid-base reactions and the behavior of different chemical species in solution.