Loschmidt constant

In chemistry and physics, the Loschmidt constant (symbol:n0) is the number density of particles (atoms or molecules) of an ideal gas at standard temperature and pressure. It is given by the relationship;n0 = P/kBT where;P is the gas pressureT is the gas temperaturekB is the Boltzmann constant The currently accepted value is;n0 = (2.686 7774 ± 0.000 0047)×1025 m−3 (CODATA 2006 value at T=273.15K and p=101.325kPa ) It is named after the Austrian chemist Johann Josef Loschmidt, who first calculated its value in 1865.
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