[ursulan]

So I attached an equation I drew on paint so hopefully it worked out.  I have no idea where the 4 carbon part is disappearing to! I know the H30+ will protonate the carbonyl O then I thought a water molecule added to the carbonyl C but then I'm stuck and can't get the answers to make sense.

[sjb]

Well, what's the structure of the "4 carbon part" missing, can you see if this can react further under your conditions?

[ursulan]

Well, what's the structure of the "4 carbon part" missing, can you see if this can react further under your conditions?

Can it just..pop off leaving a tertiary carbocation leaving the other product to be resonance stabilized resulting in the 2 different answers ie the different placements of the 18O

[sjb]

Can it just..pop off leaving a tertiary carbocation leaving the other product to be resonance stabilized resulting in the 2 different answers ie the different placements of the 18O

Sounds good, but you don't just get free carbocations floating around in solution. I'm not sure what it is you're actually asking, so I may be leading you down a blind alley. Note that due to the nature of the product you've drawn the two forms are (almost) identical.