steric factors and speed of the reaction

[Se-Young Lee]

based on steric factors alone, would it be safe to assume that atomic ions would have greater chances of forming bonds due to larger availability of its electrons, and therefore, produce faster reactions? I would assume that this logic would be consistent with the observation that many acid/base reactions tend to be quick, and would further assume that this is one of the main reasons why larger organic molecules have a tendency to react slowly and decay over time.

[irisc23]

Atomic ions and acid-base reactions would produce faster reactions due to the stronger intermolecular forces (ionic) vs for most larger organic molecules (where the strongest force is most likely dipole-dipole). Also, in larger organic molecules there are many more regions of electron density that produce repulsion, thus making it more difficult to reach the particular atom for the collision site.

I'm not sure exactly what you mean by larger availability of electrons, that is only true for anions and not cations. But you want to have a reaction involving both negatively charged and positively charged species if you want to make it happen fast, as that would give you strong electrostatic attraction and make it overcome the steric requirements more easily.