The influence of the ionic activity on the formation of ClNO2 from the uptake of N2O5 on salt solutions

N2O5 decomposes after the absorption on wet aerosols or solutions to NO2+ and NO3- (...) NO2+ reacts with water producing HNO3 (reaction 2a) and, in the presence of NaCl producing ClNO2 (reaction 2b, which decomposes to NO2+ and Cl- slowly (reaction 3). At 18 C and very low ionic strength we evaluate k2b/k2a = 1160+/-40 ... Adding NaNO3 all variations of this ratio can be explained by the influence of the ionic strength. Adding Na2SO4 we had to include a third reactio patway (2c) with k2c/k2a = 1200+/-70 at very low ionic strength.