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Topic: DETERMINING UNKNOWN ACID  (Read 3588 times)

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Offline r4bbit_

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DETERMINING UNKNOWN ACID
« on: March 09, 2008, 07:21:52 PM »
HI, our school is making us determine an unknown acid's identity
So far I've done everything possible and the following r my results:

molar mass of 67 g/mol
monoprotic
Pka of 4.4
soluble in water
weak acid
solid at room temperature
melting point of 135
boiling point around 140
produces ester with ethanol

But i just cannot find the acid, if anyone knows where i should look or anything please reply!

Offline Arkcon

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Re: DETERMINING UNKNOWN ACID
« Reply #1 on: March 09, 2008, 07:33:44 PM »
Wow, performed all those analytical tests by yourself, and still missing an important part of the puzzle.  OK, lets try this, pick a couple of your favorite analyses and tell us what they tell you.
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline r4bbit_

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Re: DETERMINING UNKNOWN ACID
« Reply #2 on: March 09, 2008, 07:40:46 PM »
Well, what I am absolutely certain is that it is monoprotic and its molar mass is 67 g/mol or something around there. This I know for a fact because I did 2 titration curves (monitored using pH probe) and there was a S curve, as well, I've done 4 titrations, 2 using 0.05M and 2 using 0.1 M of NaOH. So molar mass I am most certain. Melting point should be fairly accurate. pKa is only an approximation because the endpoint was hard to locate on the curve.

Offline azmanam

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Re: DETERMINING UNKNOWN ACID
« Reply #3 on: March 09, 2008, 08:59:27 PM »
Cross posted.  See my response in the ochem section.
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Offline Borek

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Re: DETERMINING UNKNOWN ACID
« Reply #4 on: March 10, 2008, 03:57:16 AM »
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