The absorption of water by gelatin. Part II

Abstract

A system containing H+, OH-, Na+, and NO3- was considered. Three variables influencing water absorption were examined: pH, temp., and concentration of NaNO3. NaNO3, up to 0.6 M. in the presence of HNO3, supressed swelling. At greater concentration its effect depended on ph. NaNO3, up to 0.1 M, in presence of NaOH, suppressed swelling. Increasing nitrate increased swelling in direct proportion. In both cases, swelling is an exponential function of the temp. At pH 5.0 swelling in NaNO3 solution is proportional to the log of the concentration, at greater concentration swelling is directly proportional to concentration.