mole (unit)

The mole (symbol: mol) is the SI base unit that measures an amount of substance. One mole contains Avogadro's number (approximately 6.022) entities.A mole is much like "a dozen" in that both are absolute numbers (having no units) and can describe any type of elementary object. The mole's use, however, is usually limited to measurement of subatomic, atomic, and molecular structures; tradition and its hugeness compared to more common units make it impractical for other uses.
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