[Dex]

Hi every one
I have a composition of two different fatty acids or maybe kind of paraffin that is solid in room temperature. When I poured boiled water on it, it turned to liquid with two different phases, one white color and another one green-yellow. The green-yellow one was lighter that the white one. When the temperature came down to 50-54 Celsius the white one turned to solid but the yellow one was still liquid.
By the way none of them smell that much. They solve in Acetone.

Based on above evidences, could anyone help me out to get me closer to the answer???
Could IR test help??
Any kind of help is really appreciated
Best

[discodermolide]

You mean you melted the mixture by heating it to the BPt. of water? Or you poured boiling water into it?
In the first case you would get 2 phases, in the second three, unless one of the components is water soluble.
In fact the best thing to do is to separate the phases when they are molten and examine them separately.

[Dex]

I accidentally poured boiled water into it, and I saw there are two different kind (color) of fat on the surface of the boiled water. By passing the time, the Yellow-green phase came on the top on the white phase.

[Dex]

First I thought it's Stearic acid, but by examining Stearic Acid, I realized that I was wrong because of the obvious smell of Stearic acid. And As I told before my composition does'n't smell that much.
Somehow I know that, it's made of two different fat, one as the main and another one in order to decrease the strength of the main solid.

[discodermolide]

Then you need to gat a separating funnel and isolate the three layers. Then examine them individually.
http://en.wikipedia.org/wiki/Separatory_funnel

[Dex]

Dear discodermolide
tnx for your reply. What do you mean by ''examining''?? What kind of tests should I run?? I'm mechanical engineer and not expert in chemical tests . Could you specify the examination??
By the way, based on the evidence above and being solid in room temp, now I realized that it must be saturated fatty acid or parrafin, Am I right?? ''Saturated fatty acids tend to be solid at room temperature and their melting points increase with increasing chain length'' based on http://en.wikibooks.org/wiki/Structural_Biochemistry/Lipids/Fatty_Acids#Saturated_Fatty_Acid

[discodermolide]

Well you would be best to run a mass spectrum of the compounds, this will give you the molecular weight. A ¹³C-NMR may help, an IR as well. The MPt. is essential. then you can compare with known compounds.

[Dex]

Tnx dear
I'll do it and bring back the results

[Dex]

Hi
I wanna know how can I realize that something is paraffin or fatty acid?? Is there any simple way for realize their difference? What is the difference?

[Enthalpy]

You can find both descriptions at Wiki under the names you give. They are quite different.

Under "realize the difference", do you mean: know the nature of a physical compound you have? Or distinguish them from their formula on paper? Or something else?

[Dex]

Dear Enthalpy
Under "realize the difference" I mean, I have a fatty solid in room temperature, How can I know if that is a Paraffin or Fatty acid??

[Dex]

I can't believe there is no one here, who tells me how to figure out if my material is fatty acid or Paraffin??
Unfortunately my major is not chemical engineering and I was told that people here are experts in chemical. So I expected more. but tnx anyway
Don't they smell different?? Don't their taste are different??? or anything else?

[sjb]

I can't believe there is no one here, who tells me how to figure out if my material is fatty acid or Paraffin??

Enthalpy's guidance seems good.

[Arkcon]

Dex:, I hope you don't mind I've merged your two threads, so we have all our information on one thread.  You appear to be looking for a simple chemical reaction test for long solid alkane (the paraffin wax) vs a long solid carboxylic acid (the fatty acid.)   Sometimes, a basic test is included in an organic chemistry text book.  Trying to get the absolute identity, how long the carbon chain is, to determine the name of the solid, will be harder.  Unless its a mixture of a number of chain lengths, which will make the problem very difficult indeed.  It would be helpful if we had more information -- and fyi, for the hundreds or thousands of possible carbon chains, a slight-greenish yellow color, really doesn't narrow it down very much.

[Dex]

Arkacon
tnx for your time. I do really appreciate it.
I'll try to obtain more information and come back again