In their work on collision, Trautz and Lewis explained how chemical reactions occur and why they have different reaction rates. This work is an example of

A scientific theory is a well-tested, widely accepted explanation of how or why something happens in the natural world. Trautz and Lewis’s work explains how collisions between particles lead to chemical reactions and affect reaction rates, so it is an example of a theory. A law describes a pattern or relationship, but does not explain why it occurs.

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