Collision Theory Model - Assumes that the rate of any step in a reaction depends on the frequency of collisions between the particles involved in that step.  This can be used to explain the rates of chemical reactions

The Kinetic Molecular Theory assumes that the number of collisions per second depends on the number of particles per liter.

• Therefore, in a single step reaction, the concentrations of the of both reactants should be directly proportional to the formation of the product.

• In any single given step of a multi-step reaction, the rate should be directly proportional to the concentrations of the reactants consumed in that step.

Rate-Limiting Step - The slowest step in a multi-step reaction which literally limits the rate of the reaction because the reaction cannot proceed any faster than its slowest step.

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