Naturaleza y Tecnología
The first and a recent experimental determination of Avogadro's number
Resumen
ABSTRACT
It has been almost two centuries since Avogrado presented his
hypothesis, then, more than fifty years later Austrian Loschmidt
developed a method for measuring the diameter of air molecules which
was a big step for calculating a first approximation of the amount of
molecules or atoms per unit volume. Computing Avogadro’s with
Loschmidt’s diameter results give ten times the real value. It was until
the beginning of the 19th century when Jean Perrin measured an
accurate value of Avogadro’s constant, which is the amount of
elementary entities in one mole of substance. After him, many scientists have measured this constant using more accurate methods, one of them is the X ray diffraction method, which can reach accuracy of 99.99% as using 28Si.
Key words: Avogadro’s constant, Avogadro’s number, Loschmidt,
Texto completo:
PDFReferencias
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