Definition

This law changes the concentration of a class depending on an other class concentration (or eventually itself), and two fix coefficients $ k $ and $\alpha_k$ as shown here:

$ \frac{dC_i}{dt}=k C_j^{\alpha_k} $

Classic use

Numerous solutes have a first-order kinetics with an equation similar to :

$ \frac{dC_{Ni}}{dt}= - k_{Ni} C_{Ni} $

where $ k_{Ni} $ is the reaction constant (which is the inverse of a time). For instance, bacteriological oxygen demand (DBO_5 $ $), has a constant around 0.3 days ^-1 . This degradation models the process of water auto-purification in streams.

Specifications

• Law’s ID : 201
• Number of acting classes : 2
• Number of parameters : : 2

Acting classes :

• $ C_i $ : the class modified by the law
• $ C_j $ : the parameter class of the law

Parameters :

• $ k $ : reaction constant
• $ \alpha_k $ : reaction order