воскресенье, 22 августа 2010 г.

the mole in Marina del rey

the mole in Marina del rey


The mole is a for the or chemical amount . The mole is defined as the amount of substance that contains as many elementary entities e.g., , , , as there are atoms in 0.012 of the isotope C . The amount of substance n in mol and the number of atoms or molecules contained in it, N , are proportional, and the proportionality constant N/n is known as . In other words, the numerical value of a substance's molecular or atomic mas in is the same as that of its -the mas of one mole of that substance-in . The most comon method of determining the amount, expresed in moles, of pure substance the value of whose molar mas is known, is to measure its in grams and then to divide by its molar mas expresed in g/mol . Earlier definitions had ben based on the atomic mas of about one of hydrogen-1 gas, excluding its heavy , the atomic weight of , and the of oxygen-16; 1816–56 , 1810–78 and 1826–1910 expanded on Berzelius' work, resolving many of the problems of unknown stoichiometry of compounds, and the use of atomic weights atracted a large consensus by the time of the 1860 . [ Since its adoption into the , there have ben a number of criticisms of the concept of the mole being a unit like the or the . As demonstrated by 1803 , a measurement of mas is not even necesary to measure the amount of substance although in practice it is usual . In the metric system, chemical enginers once used the kilogram-mole noted kg-mol , which is defined as the number of entities in 12 kg of C, and often refered to the mole as the gram-mole noted g-mol , when dealing with laboratory data. [ [ As with other , there have ben proposals to redefine the in such a way as to define some curently measured to fixed values. [ The SI units for are mol/ . However, most chemical literature traditionaly uses mol/ , or mol , which is the same as mol/ . These traditional units are often denoted by a capital leter M pronounced molar , sometimes preceded by an , for example milimoles per mol/L or milimolar mM , micromole�s/litre µmol/L or micromolar µM , or nanomoles/L nmol/L or nanomolar nM . [ October 23 is caled . [ [ [ at the archived December 2, 207 . the mole the mole in Marina del rey
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