Re: Organic Chemistry Lab possible Propanoic Acid?

On 29 Jun 2005 16:09:38 -0700, vumpler@xxxxxxxxx wrote:

>Hello everyone,
>
>I'm new here and plan to hopefully hang out and help when I can, but I
>have a question to start off.
>
>Today we had our lab final and we won't hear our results back for over
>a week and I can't stand to wait any longer. I know I probably failed
>it, but I still want to know what it would have been :( So here is the
>link to the actual printout we took to lab.
>[url=http://www2.volstate.edu/chem/2010/Labs/Lab_final.pdf]It is in PDF
>format[/url]
> It was a qual lab and I'll give you my results from what I can
>remember off the top of my head...
>
>Ok when you open that you'll see the writeup and then you'll see the
>solubility portion. All 4 of these appeared to be soluble, but he
>informed me that these tests should be taken with a grain of salt and
>not carved in stone. So i used them as a reference at the end.
>
>I tested my unknown on blue and red litmus paper and there was no
>change.
>

thus it is not propionic acid?


>
>Under the category of Functional Group tests: I only had 3 positives:
>The Test for unsaturation-reaction with Br[sub]2[/sub] was a positive.


thus it is not propionic acid?


>
>The Test for Organic Acids was a positive.
>The Test for Aldehydes and Ketones was a positive.
>
>The rest were negative. Therefore yeilding it was not an Aldehyde.
>
>The boiling point was right on 141[sup]deg[/sup]C.
>
>I suspect it was Propanoic Acid, yet I have no idea.

You have not tried to explain the logic of your answer, so
I didn't bother to check your pdf file.

Did you run knowns thru each test?



>everything else
>seems to conflict.

One good test that is negative disproves the hypothesis.

bob



>When I had the precipitate form in the aldehyde
>ketone test I was supposted to take a melting point on it, but I did
>not due to running out of time so I had to guess when I turned in my
>results. I went with Propanoic Acid. The problem is since I had the
>precipitate form (the solution did not turn clear by the way) doesn't
>that mean that the only derivative that it could be is a
>dinitrophnylhydrazone?
>
>Thanks.

.

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