Why H2SO4 is less stronger than HClO4?

Sulfuric acid (H2SO4) is considered less strong than perchloric acid (HClO4) due to differences in the strength of their respective conjugate bases. The conjugate base of sulfuric acid (HSO4-) is a weaker base compared to the conjugate base of perchloric acid (ClO4-), making sulfuric acid less likely to donate protons and therefore less strong as an acid. Additionally, perchloric acid has a more electronegative central atom (chlorine) compared to sulfuric acid, leading to stronger and more polarized O-H bonds in perchloric acid, contributing to its greater acidity.