Suchergebnisse

The possibility of oscillating chemical reactions is discussed, and it is shown that in systems where only first order reactions occur oscillations around equilibrium states or stationary states are not possible. For systems described by non-linear differential equations, on the other hand, it is known that oscillations around stationary states can occur, since the equations of Volterra can be interpreted as describing a set of chemical reactions. The necessary and sufficient conditions for the occurrence of oscillations in a chemical system is derived as inequalities among the rate constants, using the criterion of Sturm. It is pointed out that none of the chemical reactions alleged to show oscillatory behaviour have been thoroughly investigated experimentally.

The stationary state of electrodiffusion in a finite system is discussed. It is shown that the effect exists only in the presence of a second electrolyte which does not itself contribute to the electro-diffusion process.
The electric current through the system is calculated and is shown to contain essential terms due to the second electrolyte and to the divergence of the electric field. The variation in the effective diffusion coefficient due to the influence of these two factors is found to be very small.
In an alternating field, the electric current is shown to contain a rectified component and a first harmonic which could in principle be used for the experimental determination of the rate constants of ionic reactions.