If, for example, we take the Avogadro constant of roughly 6.022 ?10 23 we're writing things in the order sign; significand; base; signOfExponent; exponent, and writing both the exponent and its sign in small letters-even though ( again from a scientific perspective ) they're much more important than the significand.
32.
If the kilogram had been defined as a precise quantity of gold or bismuth atoms deposited with an electric current, not only would the Avogadro constant and the atomic mass of gold or bismuth have to have been precisely fixed, but also the value of the elementary charge ( " e " ), likely to ( from the currently recommended value of ).
33.
The 21st General Conference on Weights and Measures ( CGPM, 1999 ) placed these efforts on an official footing, and recommended " that national laboratories continue their efforts to refine experiments that link the unit of mass to fundamental or atomic constants with a view to a future redefinition of the kilogram . " Two possibilities have attracted particular attention : the Planck constant and the Avogadro constant.
34.
Conversely, an electronic " definition " of the kilogram ( see " Electronic approaches ", below ), which would precisely fix the Planck constant, would continue to allow 83S ! moles of 12 C to have a mass of precisely one kilogram but the number of atoms comprising a mole ( the Avogadro constant ) would continue to be subject to future refinement.
35.
Avogadro is a more flamboyant character, an ecclesiastical lawyer but part-time revolutionary . . . still, he found the time to imagine Avogadro's Law, for which he never received credit during his lifetime : now, it is considered one of the bases of modern chemistry, hence the Avogadro constant named in his honour . ( talk ) 23 : 29, 25 June 2010 ( UTC)
36.
Other prominent physicists include : Amedeo Avogadro ( most noted for his contributions to molecular theory, in particular the Avogadro's law and the Avogadro constant ), Evangelista Torricelli ( inventor of barometer ), Alessandro Volta ( inventor of electric battery ), Guglielmo Marconi ( inventor of radio ), Ettore Majorana ( who discovered the Majorana fermions ), Carlo Rubbia ( 1984 Nobel Prize in Physics for work leading to the discovery of the W and Z particles at CERN ).
37.
The fact that how fast reactions occur can often be specified with just a few concentrations and a temperature, instead of needing to know all the positions and speeds of every molecule in a mixture, is a special case of another key concept in physical chemistry, which is that to the extent an engineer needs to know, everything going on in a mixture of very large numbers ( perhaps of the order of the Avogadro constant, 6 x 10 23 ) of particles can often be described by just a few variables like pressure, temperature, and concentration.
