Avogadro

Amedeo Avagadro was a 19th-century Italian physicist. He hypothesized that equal volumes of gases under identical conditions of pressure and temperature contain the same number of molecules. This hypothesis, which became one of the basic concepts of the atomic theory of matter, is known as Avogadro's law. Later, other physicists determined that the number of molecules in the gram molecular volume, or the "mole," is the same for all gases. That number — known as Avogadro's number — is 6.02x10²³. Each year in America, from 6:02 AM to 6:02 PM on 10/23, the mole is celebrated by chemists, mathematicians and physicists. It is part of National Chemistry Week, observed annually from the Sunday through Saturday in October in which the 23rd falls. Happy National Mole Day!

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