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What Is Mole Day?

Celebrated annually on October 23 from 6:02 a.m. to 6:02 p.m., Mole Day commemorates Avogadro's Number (6.02 x 1023), which is a basic measuring unit in chemistry. Mole Day was created as a way to foster interest in chemistry. Schools throughout the United States and around the world celebrate Mole Day with various activities related to chemistry and/or moles.

For a given molecule, one mole is a mass (in grams) whose number is equal to the molar mass of the molecule. For example, the water molecule has an molar mass of 18, therefore one mole of water weighs 18 grams. Similarly, a mole of neon has a molar mass of 20 grams. In general, one mole of any substance contains Avogadro's Number of molecules or atoms of that substance. This relationship was first discovered by Amadeo Avogadro (1776-1858) and he received credit for this after his death.

Browse this website to find out more about The National Mole Day Foundation, how to become a member or just to read some mole jokes.