| − | Avogadro's number represents the number of [[atom]]s or [[molecule]]s in one [[mole]] of a given substance. It is approximately equal to 6.0221415 × 10^23. It is defined as the number of [[carbon]]-12 [[atom]]s in 12 [[kilogram|gram]] of carbon. | + | Avogadro's number represents the number of [[atom]]s or [[molecule]]s in one [[mole]] of a given substance. It is approximately equal to 6.0221415 × 10^23. It is defined as the number of [[carbon]]-12 [[atom]]s in 12 [[kilogram|grams]] of carbon. |