Question

Which of the following is the strongest acid in aqueous solution?

A. H3PO4
B. H3AsO4
C. H3PO3
D. H3AsO3
E. H3SbO4

please explain your reasoning! thanks!

Answer 1

There are only a few strong acids in water, they are:
HBr, HCl, HI, HNO3, HClO4 and H2SO4 (for the first H only)
All other acids are weak acids.

Answer 2

H3PO4 is the strong among the given acids....Look at the electronegativity of the metals and stability of conjugate base...The higher electronegativity here is for Phosphoros..and thee are two acids..H3PO4 and H3PO3...among these two look at the stability of conjugate base...PO4- and PO3-...negative charge is more distributed in PO4- and so is more stable...So H3PO4 is more stable...