\(\underline{\text { Solution: }}\)
The species \(\mathrm{Cl}_{2} \mathrm{O}_{7}, \mathrm{SO}_{2}\) and \(\mathrm{P}_{4} \mathrm{O}_{10}\) are the anhydrides of \(\mathrm{HClO}_{4}, \mathrm{H}_{2} \mathrm{SO}_{3}\) and \(\mathrm{H}_{3} \mathrm{PO}_{4}\) respectively. The acid strength of these acids follows the order \(\mathrm{HClO}_{4}>\mathrm{H}_{2} \mathrm{SO}_{3}>\mathrm{H}_{3} \mathrm{PO}_{4}\). The corresponding anhydrides also follow the same order.
