[nemzy]

A hydrocarbon that has lots of double bonds takes more energy to melt, so therefore takes more heat than a hydrocarbon with less double bonds right?

so a hydrocarbon with no double bonds will require the least amount of energy, so the last amount of heat

is my concept right?

thanks

[movies]

This depends on a lot of different factors, including crystal structure.  I don't think that your assumption is necessarily true for all compounds.

[Mitch]

Ethene will take less energy to melt than octane. Be careful how you order these things.

[nemzy]

ok, well here is the exact details of the problem:

which fatty acid melts at the highest temperature (solid to liquid)

(order from lowest to highest temp required to melt)
Don't know how to draw on here, so i will just explain it to you

1) a 17 long hydrocarbon chain with a Carboxyl group attached at the end.  Has no double bond

2) a 17 long hydrocarbon chain with a Carboxyl group attached at the end.  Has 1 double bond

3) a 17 long hydrocarbon chain with a Carboxyl group attached at the end.  Has 2 double bonds.


My guess is that 1 requires least and 3 requires most temperature