Reaction probabilities of gaseous nitrous acid, HONO, with HCl, HBr, and HI treated ice surfaces have been investigated in a fast flow-tube reactor coupled with a differentially pumped quadrupole mass spectrometer (QMS) at 191 K. The reaction probability increases with the HX surface coverage, and the rate is the highest for the HONO reaction on the HI-treated ice surface. Relative rate constants are correlated to the nucleophilic parameter, according to the linear free-energy relationship for this series of heterogeneous reactions on ice surfaces. The correlation was also extended to HOCl + HX(ad) reactions on the ice surface, and it can be used to treat other heterogeneous atmospheric and catalytic reactions. The reaction products CINO and BrNO were determined by the QMS. INO was found to rapidly convert to 12 on surfaces, and I-2 was observed from the reaction of HONO + HI. The uptake coefficient cf I-2 on the HI-treated ice surface is higher than that for I-2 on the water-ice surface.