The model contains one compartment called "compartment". There are four species named S1, S2, S3 and S4 and two parameters named k1 and k2. 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 × 10−6 mole
Initial amount of S2 1.5 × 10−6 mole
Initial amount of S3 2.0 × 10−6 mole
Initial amount of S4 0.5 × 10−6 mole
Value of parameter k1 1.3 × 106 litre mole-1 second-1
Value of parameter k2 0.3 × 106 litre mole-1 second-1
Volume of compartment "compartment" 1 litre

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