Impacts of sea-salt-aerosol pH on oxidation processes, sulfur cycling, and surface-ocean fertilization are uncertain; estimates vary from pH <1 to > 9 and the pH-dependence of some transformations is poorly characterized. We modeled these processes under clean and polluted conditions. At pH 8, S-(IV) + O-3 in sea salt is the principal S-oxidation pathway. At pH 5.5, S-(IV) oxidation by HOCl dominates. Decreased SO2 solubility at pH 3 slows S-(VI) production. The relative contribution of H2SO4(g) scavenging to S-(VI) in sea salt increases with decreasing pH. Significant sea-salt dehalogenation is limited to acidified aerosol. Volatilization rates of BrCl and Br-2 do not vary significantly between pH 5.5 and 3, whereas HCl production via acid displacement increases by a factor of 20. At pH 5.5 and 8, virtually all HNO3, is scavenged by sea sail. Modeled HNO3 increases at pH 3 but remains substantially lower than particulate NO3-. Discrepancies between measurements and modeled results are assessed based on measurement artifacts, uncertainties in rate and equilibrium constants, organic reactants and surface films, and dynamics.