[kekie]

I'll see things where hex- will become hexa- and -ene will become just -en. I assume the purpose of this is to make the names less cumbersome to say, but I don't know.

Is there a big list somewhere that has all these things on them, for reference?

[discodermolide]

Have you a concrete example. I know that in German the last e in ene is dropped. That is hexane becomes hexan and hexene becomes hexen. 

[kekie]

Like ethanol - why isn't it ethaneol?

[discodermolide]

That is the convention. In English I don't think you can put two vowels together.

[kekie]

So if you end up with two vowels together, which do you drop? Is there some rule to it, or is it just convention?

[discodermolide]

In this case the "e" is dropped. No doubt there is an complete english grammar available on the internet, a google search may be worth it.

[AlphaScent]

English words have two vowels all the time... e and then a is all the time

Leaves..great..tease...mean..lean

bee..been..seen..

u then i

distinguish

But my favorite is areola ...that is e then o

[AlphaScent]

Im sorry a little humor to start the day...

To answer the question though:  I have no answer.  Never really stopped to think why.  I think the reason that you are asking these questions is the reason that IUPAC was created.  To put a stop to people from other backrounds convoluting  the science just because of nomenclature.   

That is my 2 cents....

[discodermolide]

English words have two vowels all the time... e and then a is all the time

Leaves..great..tease...mean..lean

bee..been..seen..

u then i

distinguish

But my favorite is areola ...that is e then o

Just testing you:)

[kekie]

Hmm, interesting.
Thanks!
I wonder if the letter dropping/adding is actually part of IUPAC, of if it's just colloquial. Either way, while a chart would be nice, I've come to realize that - at least for me, a native English speaker - it's not really necessary.