Patient: It must be tough spending all day with your hands inside someone's mouth?
Dentist: I prefer to think of it as having my hands inside their wallet.
MoleIn 1971, the mole—the amount of substance (matter)—was adopted as a chemical measurement added to the six base quantities of the SI (International System of scientific units). The decision was made by the Conférence Général des Poids et Mesures (CGPM), the principal executive organization under the Treaty of the Meter (which dates back to the Metric Convention on 20 May 1875). IUPAC's participation was led by M.L. McGlashan. The mole is the amount of substance of a system which contains as many elementary entities as there are carbon atoms in 0.012 kg of carbon 12. The elementary entities must be specified, such as atoms, molecules, ions, electrons, other particles, or specified groups of such particles. The agreed symbol for the unit is mol, and the symbol for amount of substance is n.« |
