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How "Avogadro constant" was invented and how scientists calculated it for the first time?
Question Date: 2013-10-10
Answer 1:

Please click here on AvogadroConstant to read a wonderful answer for your question.

Answer 2:

Avogadro´s constant is the number of atoms or molecules in a mole of material. It´s also part of the definition of the atomic mass unit (amu), which is the unit given to the masses of the atomic elements.

1 amu=1/(Avogadro´s Number of grams)=1/(6.0221415x1023 grams)

Carbon has been selected as the scientific reference atom, so for carbon, there are exactly Avogadro´s number of carbon atoms in 12 grams of carbon, which is equal to 1 mole of carbon.

The first calculation of Avogadro´s constant was done by Nobel Laureate Jean Baptiste Perrin in 1909, who estimated the number based on his research in Brownian motion, which is the constant, random motion of microscopic particles in a fluid. His paper states that "The invariant number N is a universal constant, which may be appropriately designated `Avogadro´s Constant."

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