The solubility of which one of the following compounds will increase if the pH of a saturated solution of the compound is lowered?
AgF
AgCl
AgBr
AgI
Ag2SO4
2007-02-26 11:01:52 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
HBr, HCl and HI are strong acids, thus dissociate 100% in water and thus the respective ions don't hydrolyze. Therefore if you add H+ into solution you don't affect the form the ions are in and thus you don't affect the solubility.
HF is a weak acid with pKa=3.15
Also the second dissociation for H2SO4 is not 100% (pKa2=1.99)
So adding H+ will shift the equilibiria
F- + H+ <=> HF
SO4(-2) + H+ <=> HSO4(-)
to the right. This means that now the anion that comes from the precipitate is partly sequestered in a protonated form and thus more solid will be able to dissolve.
2007-02-27 00:26:53 · answer #1 · answered by bellerophon 6 · 0⤊ 1⤋