An Experiment on the Freezing of Electrolyte-Containing Water Droplets

Abstract

In order to investigate the influence of the impurities dissolved in water droplets upon their freezing, the following experiment was carried out : aqueous dilute solutions of electrolyte were dispersed, with the aid of a nebulizer, to fogs of droplet size of 8μ diameter in average, and their freezing temperatures were observed in a thermostatlike cold chamber maintained at temperatures from -5°to -40°C. As for the electrolytes used, NaCI, NaBr, NaI, KCI, KBr, and KI were selected as the 1 to 1-valent type salt, BaCl₂, BaBr₂ and BaI₂ as the 2 to 1-valent type salt, and further, A1C1₃ and A1Br₃ as the 3 to 1-valent type salt.
The results were such that (1) the freezing temperature varies with the concentration of electrolyte, and the highest temperatures are found at the concentrations of approximately 10^-4, 10^-6, and 10^-8N for 1 to 1-, 2 to 1- and 3 to 1-valent type salts, respectively; and (2) with the electrolytes tested, the freezing temperature falls into the series I^- (highest) >Br^->Cl^- (lowest) so far as the same metal ion is concerned.