Chemistry Lovers Celebrate Mole Day

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Students in Chemistry Lab

Thousands of students across the country celebrate Mole Day on Oct. 23. Corbis hide caption

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It doesn't dig underground and it's not above Cindy Crawford's lip. But the mole — a fundamental unit in chemistry — is the guest of honor today at 5,000 schools across the country.

A mole is the number 6.02E23 (602000000000000000000000.) It's big, especially in chemistry where most numbers are really small. The mole is used to convert those really small numbers into something chemists can work with.

"The atom is so so small you can't possibly measure one atom," says Nancy Hinrichsen, a chemistry teacher at Cherry Hill East in Cherry Hill, N.J. "If you had a huge number of atoms, then you could measure the mass. So the mole — if you were looking at the atomic mass of an element — that amount in grams is one mole."

A mole of any element equals that element's atomic mass, which you can find on a periodic table. Take carbon for instance. The atomic mass of carbon is 12. That means 12 grams of carbon equals one mole. The same goes for oxygen (16 g = 1 mol) and nitrogen (14 g = 1 mol.)

But moles aren't limited to chemistry.

"You can have a mole of chocolate chips. You could have a mole of people, you could have a mole of donuts," says Hinrichsen. "You could have a mole of anything. It just makes particular sense in chemistry, because the size of the atom is so small."

It's a hard concept for students to remember. In 1991, retired science teacher Maury Oehler, from Prarie du Chien, Wisconsin, created a holiday for the mole.

"In chemistry, the mole is probably the most important concept," Oehler says. "It's celebrated on Oct. 23 because 10 to the 23 power is Oct. 23. And it's celebrated from 6:02 a.m. to 6:02 p.m."

The holiday now has a theme. This year it's Mole Madness, after the basketball tournament, and mole-themed food, says Tom Tweedle, Mole Day Foundation executive director.

He says his students enjoy "le-mole-ade, guaca-mole, pie-a-la-mole, and ani-mole crackers."

Tweedle lives in Millersport, Ohio. From 6:02 this morning to 6:02 tonight, the town of Millersport will be renamed Molersport.

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