Density and viscosity of sodium + ammonia and ammonium iodide + ammonia solutions

Abstract

The densities and viscosities of the Na + NH₃ and NH₄I + NH₃ solutions were measured as a function of temperature and composition. In the NH₄I + NH₃ system, the density and viscosity increase with NH₄I concentration, while those of the Na + NH₃ system decrease with increasing sodium composition. The concentration dependence of viscosity is discussed in terms of the theory of transport processes based upon a small step-diffusion process. Liquid NH₃ near the boiling point can be described as a rigid-sphere liquid. The calculated viscosities are in qualitative agreement with the experimental data.