Mole day is a special day in chemistry classes around the United States.  Usually it is celebrated on October 23 from 6:02 on the morning to 6:02 at night.   The date and time is represented by Avogadro’s number (6.02 x 10^23) a measuring unit used in chemistry.  Since the spring semester chemistry class is not in session during October,  they celebrated the special day during April 9.