Mole Day is an unofficial holiday celebrated among chemists, chemistry students, and chemistry enthusiasts on October 23, between 6:02 a.m. and 6:02 p.m., making the date 6:02 10/23 in the American style of writing dates.
The time Mole Day and date are derived from the Avogadro number, which is approximately 6.02×1023, defining the number of particles (atoms or molecules) in one mole (mol) of substance, one of the seven base SI units.
The originated in an article in The Science Teacher in the early 1980s. Inspired by this article, Maurice Oehler, a high school chemistry teacher from Prairie du Chien, Wisconsin, founded the National Foundation (NMDF) on May 15, 1991.
Many high schools around the United States, South Africa, Australia, and Canada celebrate as a way to get their students interested
The American Chemical Society sponsors National Chemistry Week, which occurs from the Sunday through Saturday during which October 23 falls. This makes Mole Day an integral part of National Chemistry Week.
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. Find ways to celebrate this chemistry “holiday” with the links below.
Mole Day also typically falls during National Chemistry Week—an annual event that unites American Chemical Society Local Sections, businesses, schools, and individuals in communicating the importance of chemistry in everyday life.
National Mole Day Foundation is your go-to source for all things Mole Day. Jokes, history, themes, store—they’ve got it all. Don’t miss the “Fabulous Mole Projects” gallery
- Just in case you wanted to dedicate part of Mole Day to, you know, learning something… Take a look at this collection of worksheets, puzzles, and labs about moles.
- Molar Whack
Chemistry meets the arcade in this online game. Whack a mole on the head—how many points can you earn? (Tip: Hit elements with the highest molar mass!)