Interdiffusion coefficients of thallous sulphate and orthophosphoric acid in H2O and D2O at 35°C by a radioactive tracer technique

Anomalies in the ion transport of phosphoric acid in water and heavy-water environments

“…In the present measurements care has been taken to avoid such disturbances. In order to check the unexpected low value of the diffusion coefficient near 0.8 M concentration, measurements were made over the concentration range from 0.6-1.0 M in steps of 0.1 M. This confirmed the occurrence of the anomalously low value of the diffusion coefficients near 0.8 M. Such a lowering of the diffusion coefficient at a concentration of 0.84 M has also been reported in the work of Das and Changdar [5] at a temperature of 35 • C in both water and heavy-water environments though they did not investigate the concentration range 0.6-1.0 M so thoroughly and did not make any conclusive inference regarding the anomaly in the diffusion data. According to them the depression was possibly due to the effect of hydration at the particular concentration.…”

“…The curves X and Y represent the present set of data. In the inset the data of Das and Changdar [5] are given. It can be seen that the ions diffuse faster in water (X) than in heavy water (Y).…”