safc
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Melting Points
Hello. I am currently doing my A Level studies and have just done an experiment to determine the melting points of Benzoic Acid and Urea.
I feel I could do with getting the right values to compare, does anyone know the correct values?
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vulture
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Melting point of benzoic acid should be 122C, urea should be between 132-135C.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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BLAST_X
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The melting point of urea can`t determine
correctly, because the temperature of
decomposition are below boiling point.
You can say approximately:
melting point = 133 C, but
termal decomposition > 132 C !
all you need is C - H - O - N
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Polverone
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Things may be somewhat complicated by its decomposition, but urea does not decompose very quickly when held at its melting point. I have melted urea
without difficulty. At higher temperatures, or under the influence of catalysts, it will indeed decompose with considerable rapidity.
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BLAST_X
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good description ! 
I haven`t want say it`s utterly impossible.
This many factors are the cause, when you measure the mp of urea, it`s different always a bit.
all you need is C - H - O - N
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