The model contains one compartment called "compartment". There are four species named S1, S2, S3 and S4 and two parameters named k1 and k2. Compartment "compartment" is 1-dimensional. All four species are declared to have only substance units. The model contains two reactions defined as:

Reaction Rate
S1 + S2 → S3 + S4 k1 · S1 · S2
S3 + S4 → S1 + S2 k2 · S3 · S4

The initial conditions are as follows:

Value Units
Initial amount of S1 1.0 × 10−2 mole
Initial amount of S2 1.5 × 10−2 mole
Initial amount of S3 2.0 × 10−2 mole
Initial amount of S4 1.0 × 10−3 mole
Value of parameter k1 6.2 × 102 mole-1 second-1
Value of parameter k2 5 × 102 mole-1 second-1
Length of compartment "compartment" 1 metre

The species have been declared as having substance units only. Thus, they must be treated as amounts where they appear in expressions.