Popular Science
355

A more perfect unit: The New Mole

THE MOLE-as in 6.02214076×10^23, the unit in chemistry used to count really really tiny stuff like atoms and molecules. Well, THE MOLE changed (it's not simply 6.022x10^23 anymore). And while you may not have noticed it, a fundamental shift in the way we measure things-not just on Earth, but throughout space and time-took place when the new mole was born.

Science Picks