Chemistry Reference
In-Depth Information
Fig. 6.8 “Solid-State Model Kit” of the Institute for Chemical Education, Univ. of Madison [
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Dynamic models: Simulation games are dynamic models. They allow the
demonstration and interpretation of physicochemical processes on the particle
level, unlike the much discussed structural models, which only represent static
and time-independent aspects of matter. The processes, which will be simulated on
the model level below, can be divided into two categories:
- Processes in which particles (atoms, molecules, ions, photons, etc.) move in
space without transforming into other particles. Examples: diffusion, chroma-
tography, distribution equilibria, mixing and separation processes,
light
absorption.
- Processes in which particles transform into other particles during a chemical
reaction. The time behavior of the system, i.e. the kinetics of these reactions are
of particular interest. Examples: reactions of elements, consecutive reactions,
competing reactions, balanced reactions, oscillating reactions.
The particles are being represented by simplest models in both categories. It is
not so much the behavior of the single particle that is of primary interest, but the
statistic behavior of a particle arrangement. From this point of view the simulation
games can also be called statistic games. The rules for these games are simple, they
can be described with the following basic points:
- One can either win tokens from a playboard (board model) or balls from a vessel
(urn model).
- A randomly hit particle is considered to be activated - what happens to it next
depends on the rules of the game: moving a sphere on the playboard, converting
it into another kind of sphere by color change, etc. - the rules should be assigned
to the simulated process in a comprehensible way.
- Every event that leads to an activation counts as one time unit, regardless of its
specific consequences.
- The kinetics of the statistical process are being recorded by writing down the
status of the game depending on the number of time units.
