The answer is Avogadro.
Step-by-step explanation:
Here are the examples :
The mass of a single carbon-12 atom has been found to be 1.992×10^-23 g using a mass spectrometer. The number of atoms in exactly one mole of 12C is 6.02×10^23. This can be shown by the following calculation.
Na = Mass per mole of 12C ÷ Mass of one atom of 12C
= 12g/mol ÷ 1.992×10^-23
= 6.02 × 10^23 mol^-1
Thus one mole of any substance contains 6.02×10^23 particles. This number is called the Avogadro constant.
So that 12g of the element carbon , 1 g of the element hydrogen and 32g of the element sulphur contains 6.02×10^23 atoms even though the element carbon exist as atoms, and Hydrogen and sulphur exist as molecules.
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