| Abstract
| - With use of a droplet train apparatus, the mass accommodation coefficients (α) of gas-phase HCl, HBr, HI,and CH3COOH were measured for 1-octanol to probe the nature of the hydrophobic organic surface as afunction of relative humidity and temperature (263−283 K). In the absence of water vapor, α for both HBr(g) and HI(g) is unity, independent of temperature. The mass accommodation coefficients for acetic acid andHCl are smaller, about 0.3 for acetic acid and 0.01 for HCl at 273 K, displaying negative temperaturedependence. The value of α for acetic acid is independent of relative humidity. However, values of α forHBr, HI, and HCl change dramatically as a function of relative humidity. As the relative humidity increases,the α values for HBr and HI decrease, and α for HCl increases. At a relative humidity of about 50%, α forall three species converges to that on pure water. A model is proposed to explain these unexpected results.
|
