hello
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question melting point cinnamic acid/urea
What are the mixed melting points of cinnemic acid/urea at 25:75, 50:50 and75:25? I'm not sure that I did it right.
Thanks
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Nicodem
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Hello,
you surely don't expect any of us to go and measure that for you?
Besides you can't measure the melting point of such a mixture unless it is homogenous and monophasic.
Why would you need such a useless information? (it is actually the curiosity that made me post this )
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
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The_Davster
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It sounds like hello is in some sort of beginning level college or uni organic chem course, and he/she thinks they messed up the first lab of the
course. Melting point labs are always the first lab in an organic chem course.
Am I right?
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chemoleo
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Or it is to do with forming some phenylethylamine derivative.
I can even see where a melting point might come in.
[Edited on 18-9-2005 by chemoleo]
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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12AX7
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| Quote: | Originally posted by Nicodem
Besides you can't measure the melting point of such a mixture unless it is homogenous and monophasic.
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So what's an eutectic?
Even if it shows a "mushy state", you have solidus (freezing point, below which all is solid) and liquidus (melting point, above which all
is liquid) points, so it's not an impossible question.
Tim
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Nicodem
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Chemoleo, I also had the same thought but for a Hoffman rearangement you need a satuarated amide and not a cinnamic acid amide. Besides, you need not
to know the m.p. of such a mixture to make the amide since the temperature needed is above the melting point of urea. This information is of no use
whatsoever.
edit: Tim, I agree. What I wanted to say is that I don't feel like we are here to do a whole phasic transition diagram for others. Each do his
own homework.
[Edited on 18-9-2005 by Nicodem]
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Sandmeyer
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Tim: http://en.wikipedia.org/wiki/Eutectic
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