SN2 Reactions

[DevinSandoval_1D]

For a SN2 reaction, how would you go about determining the number of steps involved, transition states and intermediates? If it helps, I am referring two question 9 on the first practice quiz.

[Joanna Su 2L]

SN2 reactions are always one step reactions. There are no intermediates. As the hydroxide attacks bromomethane, the Br-C bonds starts to break. This would give a transition state with Br-C partially broken and C-OH partially formed.

[Tanera van Diggelen 4G]

If SN2 reactions are always one step, does that mean that the new bond forms at the exact same time as the old bond breaks? Also, are there any SN reactions that are more than one step?

[Chem_Mod]

Sn1 reactions are two-step processes. For Sn2 reactions, yes, the C-O bond is forming at the same time the C-Br bond is breaking, which can be denoted by a transition state structure.

[Andrea Medina 1A]

Can sn2 occur in reactions with multiple steps?