National Mole Day is celebrated on October 23rd each year from 6:02 am to 6:02 pm, in observance of the "mole." For 2018, the Mole Day theme is "Moley Potter." The "mole" is a way of counting Avagadro's number, which is 6.02 x 10 to the 23rd power of anything (just as a dozen is a way of counting 12 of anything).
Mole Day owes its existence to a 19th century physics professor named Amedeo Avagadro. He discovered that the number of molecules in a "mole" is the same for all substances. Because of this, chemists are able to accurately measure quantities of chemicals.
Do you want to find out more about chemistry? Here are some books that you may enjoy!