Bibliography.
[L] J. D. Logan, “Applied Mathematics” or “Εφαρμοσμένα Μαθηματικά”.
[KX] Σ. Κομηνέας, Ε. Χαρμανδάρης, “Μαθηματική Μοντελοποίηση”
A chemical reaction for one reactant ([L], Chapter 1)
The reactants are transformed into products. Consider here only one reactant,
$$
A \longrightarrow \text{products}.
$$

A chemical reactor with volume $V$.
Variable.
- $C$ is the concentration of the reactant (mass per unit volume) in the reactor.
Parameter.
- $\lambda$ is the flow of reactant at the entrance of the reactor (volume of supplied material per unit time).
[Thus, $\lambda C_{\rm in}$ is the mass per unit time entering the reactor.]
Assumptions.
- The supply (volume of material) at the output is equal to the supply at the input $\lambda$ (let us imagine that the pipes coming in an out of the reactor are of equal diameter).
- Reactant has uniform temperature and it is constantly homogenized → this allows us to assume that the reactant density is $C(t)$, i.e., a function of time only.
- $\lambda$ is a constant.