There is a common misconception among educators, and even some metrologists, that the Avogadro constant _N_~A~ is (or should be) a pure number, and not a constant of dimension *N*^–1^ (where *N* is ...

The early history of chemistry has many interesting stories. Just consider the problems scientists had 200 years ago as they tried to figure out some of the most basic ideas of chemistry. It was clear ...

In addition to other scientific units, the kilogram also is now defined by a natural constant. This is made possible by single crystals grown from highly enriched silicon-28. In addition to Ampere, ...

How many atoms are there in a kilogram of silicon? This number is Avogadro’s constant and working out its value is one of the more important tasks that materials scientists face. Today, a group of ...

This release is available in German. A milestone in the international Avogadro project coordinated by the Physikalisch-Technische Bundesanstalt (PTB) has been reached: With the aid of a single crystal ...

This video is about the mole, the unit of measurement for the number of particles in a substance. The mole is the unit for amount of substance. The number of particles in a substance can be found ...

I MUST plead guilty to the charge of not having made a very deep search of the older literature in connexion with the evaluation of ‘Avogadro's Number’. This name has only come into general use in ...