MadSci Network: Engineering |
Hello Stefano, We literally had people searching from all over the world (England, Germany, Australia, Spain, and The USA) for the definition of the mg/Nmc units and finally have a definitive answer for you !!! The mg is, of course, milligrams. The mc term was a new one for me in the US. A Spanish scientist that I work with reminded that cubic meters is represented as metrico cubico, hence the mc can also be written as m^3 or cubic meters. The N term was the hardest to "nail down." The IUPAC definiton of the symbol N is a Newton (kg X m/s^2.) The IUPAC definiton of an italicized N is used to define Normality (the number of equivalents of solute per liter of solution.) However, when you put the term Newton into the formula, you have a unit that does not make any sense in this context. I have also never seen Normality used for any application other than for solution chemistry. I then contacted an editor at Pollution Engineering Magazine (E-mail: KCanning@cahners.com) who refered me to a Ph.D. in Germany named Dr. Thomas Schmidt (E-mail: schmidt@mpi-muelheim.mpg.de), who explained that the N term is an abbreviation of norm or normal. He continued to explain that "Normal, in this connection, means a temperature of 0 degrees Celsius and a pressure of 1.013 bar, the conditions at which one mole of an ideal gas has a volume of 22.413837 liters." This definition makes sense to me in conjunction with a flue gas measurement. Ken Johnson, an administrator with the MadSci Network (E-mail: kayjay45@home.net) confirmed this explantion with an environmental scientist in Australia. By comparison, we routinely use ppm (parts per million)in the USA for this type of measurement. I want to Thank You, Stefano, for helping me learn something new in the world of Chemistry. I would also like to thank all of the scientists that helped me to define this unit of measurement for you.
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