Mole Day - National
Day is Oct 23. More specifically, Mole Minute is 6:02AM on Oct
It was named Mole Day because when it the
date/time is written out ( 6:02 10/23 ) it symbolizes Avogadro's
number 6.02 x 1023 ! Mole Day has it's own
organization which features an amusing "Pledge of
The week that includes Oct 23 is generally
declared to be National Chemistry
Week and is celebrated by the American Chemical Society. In 2009 it
is the week of October Oct.18-24, and the theme is "“Chemistry
- It's Elemental".
NIST provides a definition
of the mole as well as the presently
accepted value for Avogadro's number. This is called into question by a recent study (
Ref 1 ) done in Germany. X-ray diffraction was used
to calculate the exact separation between silicon atoms in a 1 kilogram,
10 cm diameter billet of pure silicon. If the separation is accurately and
precisely known, Avogadro's number can be calculated from the known mass
and dimensions of the billet. Although the relative precision of the
measurement is good (3.4x10-7), it differs from the accepted
value by nearly three times that amount! If the precision can be improved,
and the accuracy question answered, this measurement could lead to an
absolute definition of the kilogram.
To Electrochemistry and Beyond!