Avogadro's number (ävōgäˈdrō) [key] [for Amedeo Avogadro], number of particles contained in one mole of any substance; it is equal to 602,252,000,000,000,000,000,000, or in scientific notation, 6.02252×1023. For example, 12.011 grams of carbon (one mole of carbon) contains 6.02252×1023 carbon atoms, and 180.16 grams of glucose, C6H12O6, contains 6.02252×1023 molecules of glucose. Avogadro's number is determined by calculating the spacing of the atoms in a crystalline solid through X-ray methods and combining this data with the measured volume of one mole of the solid to obtain the number of molecules per molar volume.
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