Hygroscopic behavior of wet dispersed and dry deposited NaNO3 particles

► Previous controversial studies on hygroscopic behavior of NaNO3 particles prompted this study. ► Quite different hygroscopic behavior between wet dispersed and dry deposited NaNO3 particles was observed. ► The difference is due to different, i.e. homogeneous and heterogeneous, nucleation mechanisms. ► Similar observations were also made for NaCl, KCl, (NH4)2SO4, Na2SO4, and KNO3.