The Relationship Between Order and Mechanisms
- Page ID
- 3825
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This step has a molecularity of 2 - a bimolecular reaction. The other reaction we looked at happened in a single step:
Because of the two species involved (one molecule and one ion), this reaction is also bimolecular.
Unless an overall reaction happens in one step (like this last one), you cannot assign it a molecularity. You have to know the mechanism, and then each individual step has its own molecularity. There's nothing the least bit complicated about the term molecularity. The only confusion is that you may sometimes find it used as if it meant the same as order. It doesn't!
Contributors and Attributions
Jim Clark (Chemguide.co.uk)