The Mole Concept

Providing a name for a quantity of things taken as a whole is common in everyday life. Some examples are a dozen, a gross, and a ream. Each of these represents a specific number of items and is not dependent on the commodity. A dozen eggs, oranges, or bananas will always represent 12 items.

In chemistry we have a unit that describes a quantity of particles. It is called the mole (sometimes abbreviated as mol). A mole is 6.02 x 10²³ particles. The particles can be atoms, molecules, ions, electrons, and so forth. Because particles are so small in chemistry, the mole is a very convenient unit. The number 6.02 x 10²³ is often referred to as Avogadro's number in honor of the Italian scientist whose hypothesis led to its determination.