An ongoing international effort to redefine the kilogram by 2018 has been helped by recent efforts from a team researchers from Italy, Japan and Germany to correlate two of the most precise ...

Determining the Avogadro constant with unprecedented accuracy demands a rigorous integration of complementary measurement strategies. Central to this endeavour is the x-ray crystal density method, ...

The International System of Units (with the abbreviation of SI units) is one of the foundations of modern science. It consists of seven base units from which all others can be derived. These are the ...

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 ...

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 ...

Avogadro’s number, denoted as N A, is defined as the number of constituent particles that include atoms, molecules, ions, etc. per mole of the substance. This helps in diving deep into the world of ...

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 ...