Happy #MoleDay (6:02 a.m. to 6:02 p.m.) Dive into our FREE #chemistry course and master moles -the SI unit for measuring a substance, representing a specific number of particles (e.g. ) known as Avogadro's number- and more! No lab coat needed. #STEM learn.saylor.org CHEM101: General Chemistry | Saylor Academy | Saylor Academy
Mole Day is celebrated on October 23 from 6:02 a.m. to 6:02 p.m., honors Avogadro's constant (6.02×10²³), the number of particles in a mole, a key chemistry concept. Load image
Did you know? Every year on October 23 from 6:02 a.m. to 6:02 p.m. Mole Day is celebrated. The Mole Day commemorates Avogadro's Number (6.02 x 10²³) which is also known as the Avogadro constant. Visit @RSCBhavnagar for more fun learning activities... Load image 5 KB DSTIndia and 6 others
— Regional Science Centre (RSC)Bhavanagar (@RSCBhavnagar) October 23, 2025
Happy #MoleDay folks! A mole is the Chemistry unit for the amount of substance: a mole contains 6.022 x 10"23 atoms or molecules. So, to celebrate, here’s the beautiful orange-red fluorescence of a millionth of a mole of the dye Nile Red in acetonitrile. #scicomm #RealTimeChem Load image
Replying to @PhysInHistory Happy Mole Day! Oct 23rd! Avogadro's constant (6.02×10²³) is called a mole, just like 12 is called a dozen. It's an important number because 1 mole of protons or neutrons weighs 1 gram. See my mini lecture on moles and molar mass here: youtube.com Moles and Molar Mass Explained | Chemistry Example Included
Happy Mole Day to all the chemistry lovers out there! Today we raise a beaker to the mighty 6.02 × 10²³, Avogadro’s number, the mole and the number used to define the number of atoms in one mole. #MoleDay #AvogadrosNumber Load image
Mole Day celebrates the mole, a fundamental unit in chemistry used to quantify atoms, molecules, and other particles. Established to recognize the importance of chemistry and its applications, the day encourages appreciation of scientific progress, and inspires students to widen their knowledge and curiosity in the field. The mole concept forms the basis of many chemical reactions and plays a crucial role in understanding chemical composition and reactions, making the commemoration of Mole Day relevant to both the academic and professional community.
The inception of Mole Day in the United States is attributed to an article published by Maurice Oehler, a retired high school chemistry teacher, in a 1983 issue of The Science Teacher journal. Oehler enunciated the importance of the mole concept and called for the establishment of a day dedicated to its celebration. Gaining traction, Mole Day quickly became popular among American schools and universities, with celebrations highlighting the contributions of chemistry to advancements in medicine, technology, and the environment.
Mole Day is observed in America by engaging in a variety of educational and entertaining activities. These may include hosting chemistry-themed competitions, mole-themed art contests, and educational seminars in schools and universities. Participants often get creative with puns on the word "mole," bringing light-hearted fun to the subject while enhancing the understanding of the underlying scientific concepts. In alignment with the mole unit, the day is celebrated on October 23rd, starting at 6:02 AM and ending at 6:02 PM, reflecting the scientific notation of Avogadro's number, 6.02 x 10^23.
Mole Day facts
One mole of a substance contains as many entities (atoms, molecules, or other particles) as there are in 12 grams of pure carbon-12.
If you had Avogadro's number of soft drink cans, you could cover the surface of the earth (land and sea) to a depth of over 200 miles.
The mole is used as a bridge between the atomic world and the macroscopic world of grams and liters. Chemical equations are worked in moles but often measured in grams.
The use of the mole in America is fundamental to all branches of chemistry. It allows chemists to count the number of elementary entities (such as atoms, molecules, or ions) in a specific sample.
In the U.S., the concept of a mole is applied beyond chemistry and into industries like pharmaceuticals, biotechnology, materials science, and environmental science.
Science Centers may hold public lectures and demonstrations related to the concept of the mole and its significance in chemistry.
Another fun activity is creating artwork that celebrates moles and chemistry. This could be anything from mole sculptures to mole murals.
Many schools and universities use Mole Day as an opportunity to engage students in chemistry, often holding science fairs or contests related to the subject.