Here's why:
* Avogadro's number (approximately 6.022 x 10^23) represents the number of particles (atoms, molecules, ions, etc.) in one mole of any substance.
* One mole is a unit of amount, just like "dozen" represents 12 of something.
* The mass of a single particle is its atomic mass unit (amu).
Example:
* The atomic mass of a carbon atom is 12 amu.
* One mole of carbon atoms contains 6.022 x 10^23 carbon atoms.
* Therefore, the mass of one mole of carbon atoms is 12 amu x 6.022 x 10^23 = 12 grams.
In essence, multiplying the mass of a single particle by Avogadro's number converts the mass from atomic mass units (amu) to grams, which is the standard unit for measuring mass.
