Who was Lorenzo Romano Amedeo Carlo Avogadro? He was the guy who suggested that equal volumes of gases at the same temperature and pressure should contain equal numbers of molecules. This eventually led to a new quantity for the number...

Sal introduces chemistry students to the concept of "moles." He points out that a mole is a unit of measurement that helps a student to convert between grams and atomic mass units of any substance. Sal uses the element Aluminum to...