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Old 03-21-14, 03:43 PM   #2
buffalobillpatrick
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Unfortunately, "paraffin" is a somewhat general term meaning: "approximately saturated hydrocarbons of unspecified molecular weight".

"My CRC has an old table of heats of fusion. They vary, from 30.7 cal/gm for n-tricosane (C23H48) to 39.1 cal/gm for n-pentacosane (C25H52), to 59.1 cal/gm for n-eicosane (C20H42)"

"average heat of fusion to be 37 cal/gm.

37 cal/gm x 4.184 J/cal = 155 J/gm.

(CH2):=(12+1+1) gm/mol; (14 gm/mol x 24 )= 336 gm/mol.

155 J/gm * 336 gm/mol = ~52 kJ/mol."


"On this website (http://www.hotwatt.com/paraffin.htm), I find the heat of fusion for paraffin listed as 63 BTU/lb. On this web site (http://www.iscienceproject.com/labs/...ombustion.html) I find the chemical formula for paraffin to be C36H74.

So the gram formula weight for paraffin is 506 g/mol. Converting the units, I get the heat of fusion for paraffin to be 74 kJ/mol (Please check my math!)

Todd Clark, Office of Science
U.S. Department of Energy"

Of course, I stole all of above.

BBP

Last edited by buffalobillpatrick; 03-21-14 at 03:58 PM..
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