Mole (unit) Mole (unit) The mole is the unit of measurement for amount of substance in the International System of Units (SI). Effective 20 May 2019, the mole is defined as the amount of a chemical substance that contains exactly (Avogadro's constant) constitutive particles, e.g., atoms, molecules, ions or electrons. This definition was adopted in November of 2018, revising its old definition based on the number of atoms in 12 grams of carbon-12 (C) (the isotope of carbon with standard atomic weight 12 by definition). The mole is an SI base unit, with the unit symbol mol. The mole is widely used
Stoic physics Stoic physics Stoic physics is the natural philosophy adopted by the Stoic philosophers of ancient Greece and Rome used to explain the natural processes at work in the universe. To the Stoics, the universe is a single pantheistic God, but one which is also a material substance. The primitive substance of the universe is a divine essence ("pneuma") which is the basis of everything which exists. This "pneuma", which is the active part or reason ("logos") of God, provides form and motion to matter, and is the origin of the elements, life, and human rationality. From their physics, the Stoics