Hw 6.5

[Edmund Zhi 2B]

In the reaction, H2O2 + SO3 -> H2SO5, how do you identify which one is the lewis acid and which one is the lewis base? I know what the definitions are, but how do you determine which of the reactions is the electron "donor" and which one is the "acceptor" since they merge into one molecule?

[sarahwu3a]

In the SO3 molecule, the sulfur atom has space to accept another electron pair so that in the molecule there are 4 regions of electron density in the molecule. Thus, as the electron pair acceptor it is the Lewis acid.

[Anisha Chandra 1K]

In the solutions manual, why is SO3 drawn as having 1 double bond and 2 single bonds instead of 3 double bonds?

[DTingey_1C]

Yes isn't SO3 with one double bond more unstable than SO3 with 3 double bonds? Maybe this is because it wouldn't act as a lewis acid anymore.

[Junxi Feng 3B]

I think the best way to determine is to draw out all the lewis structures. And you can see the lewis structure of the final product is still drawn around the sulfur atom, meaning it accepts the electrons. Therefore, it's the Lewis acid.