Alkenes, Alkanes pH levels (1 Viewer)

[RachelGreen]

I have a question, are alkenes and alkanes neutral and why? Also, is it because of the double bond in alkenes that makes it have a higher boiling point than alkanes?

 

[Mr_Kap]

I have a question, are alkenes and alkanes neutral and why? Also, is it because of the double bond in alkenes that makes it have a higher boiling point than alkanes?

Good question. Think what pH actlly means. It means the amount of H+ ions. pH = -log[h+].
alkanes and alkenes dont dissocate so wont produce H+ ions. That is why they are neutral

 

[leehuan]

The latter question is outside the syllabus, but yes I think the fact that there is a higher electron density in the double bond means that the dispersion forces induced are a tiny bit stronger, thus alkenes have a slightly higher BP than alkanes

 

[someth1ng]

They're neutral because the H is far too strongly bonded to the C atom for it to be acidic and if it did deprotonate, the conjugate would be extremely unstable.

Boiling points of alkanes are usually higher than the corresponding alkenes due to slightly more van der Waals forces.