Q.What is Avogadro's number?

Avogadro's number is the number of constituent particles contained in one mole of a substance: N_A = 6.022 x 10^23 mol^-1.

The mole is the SI base unit for the amount of substance. One mole of any substance is defined as the amount that contains as many elementary entities (atoms, molecules, ions, or other particles) as there are atoms in exactly 12 grams of the carbon-12 isotope. This fixed number of entities per mole is Avogadro's number (or Avogadro constant).

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