Amount of substance Amount of substance Amount of substance is a standard-defined quantity that measures the size of an ensemble of particles, such as atoms, molecules, electrons, and other particles. It is sometimes referred to as chemical amount. The International System of Units (SI) defines the amount of substance to be proportional to the number of entities present. The SI unit for amount of substance is the mole. It has the unit symbol mol. The proportionality constant is the inverse of the Avogadro constant. The mole is defined as the amount of substance that contains an equal number of elementary entities as there
The Tao of Physics what has happened. The Tao of Physics The Tao of Physics: An Exploration of the Parallels Between Modern Physics and Eastern Mysticism is a 1975 book by physicist Fritjof Capra. It was a bestseller in the United States and has been published in 43 editions in 23 languages. The fourth edition in English was published in 2000. The following excerpt from "The Tao of Physics" summarizes Capra's motivation for writing this book “Science does not need mysticism and mysticism does not need science. But man needs both.” According to the preface of the first edition, reprinted in subsequent editions, Capra