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In a previous paper the molecular content of binary water-n-alcohol nuclei has been determined from nucleation rate measurements. A strong mutual enhancement of water and alcohol in forming the nuclei was observed, although macroscopically the higher alcohols are only partially miscible with water. In this paper we replace water by n-nonane, that is, we examine n-nonane-CiH2i+1OH systems with i=2–6. Using the nucleation pulse technique nucleation rates in the range 105

In previous papers the determination of the molecular contents of critical clusters has been performed. Both unary and binary vapor mixtures have been examined. This paper describes the first study of a ternary system. Using a nucleation pulse chamber accurate measurements of homogeneous nucleation rates (105

We have measured homogeneous nucleation rates of n‐pentanol droplets in argon using the nucleation pulse chamber recently described. The nucleation rates J were measured as functions of activity a at constant temperatures in steps of about 2.5 K for 241.8

In a preceding paper we determined the molecular contents of binary nuclei from homogeneous nucleation rate measurements studing ethanol–hexanol as a nearly ideal model system. Here we report the analogous measurements for the nonideal water–ethanol system known from previous investigations to display surface enrichment of ethanol in the nuclei. The nucleation pulse technique applied allows accurate measurements of homogeneous nucleation rates in the range 105

The influence of total pressure and kind of carrier gas on homogeneous nucleation rates of 1-pentanol was investigated using experimental method of laminar flow diffusion chamber in this study. Two different carrier gases (helium and argon) were used in the total pressure range from 50 to 400 kPa. Nucleation temperatures ranged from 265 to 290 K for 1-pentanol-helium and from 265 to 285 K for 1-pentanol-argon. Nucleation rates varied between 10(1) and 10(6) cm(-3) s(-1) for 1-pentanol-helium and between 10(2) and 10(5) cm(-3) s(-1) for 1-pentanol-argon. Both positive and slight negative pressure effects were observed depending on temperature and carrier gas. The trend of pressure effect was found similar for both carrier gases. Error analysis on thermodynamic properties was conducted, and the lowering of surface tension due to adsorption of argon on nucleated droplets was estimated. A quantitative overview of pressure effect is provided.

The homogeneous nucleation rates for n-nonane-n-propanol vapor mixtures have been calculated as a function of vapor-phase activities at 230 K using the classical nucleation theory (CNT) with both rigorous and approximate kinetic prefactors and compared to previously reported experimental data. The predicted nucleation rates resemble qualitatively the experimental results for low n-nonane gas phase activity. On the high nonane activity side the theoretical nucleation rates are about three orders of magnitude lower than the experimental data when using the CNT with the approximate kinetics. The accurate kinetics improves the situation by reducing the difference between theory and experiments to two orders of magnitude. Besides the nucleation rate comparison and the experimental and predicted onset activities, the critical cluster composition is presented. The total number of molecules is approximated by CNT with reasonable accuracy. Overall, the classical nucleation theory with rigorous kinetic prefactor seems to perform better. The thermodynamic parameters needed to calculate the nucleation rates are revised extensively. Up-to-date estimates of liquid phase activities using universal functional activity coefficient Dortmund method are presented together with the experimental values of surface tensions obtained in the present study.