Kinetic Order of Degradation Reactions

time

4.

kinetic order

n

1.25

initial concentration

C

0

10.

rate constant

k

0.5

t axis max.

10.

C(t) /

C

0

= 0.0785

normalized momentary rate(t) /

C

0

= -0.3695

Many chemical and biochemical degradation reactions follow fixed-order kinetics, including orders zero, one, or

n

, where

n

need not be an integer. With the exception of first-order kinetics, which is characterized by exponential decay, the diminishing concentration versus time relationship can be described by a single formula over a range that is determined by the reactant's initial concentration,

C

0

, the reaction’s (temperature-dependent) rate constant,

k

, and the kinetic order,

n

. This Demonstration identifies the formula’s applicability range and lets you simulate and monitor the progress of degradation reactions following any kinetic order in the range 0–2.5, with different rate constants,

k

, and starting at different initial concentrations.