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
Si River to the large amount of silt carried by the river, it left behind a high layer of mud in the lower reaches of the Si River’s former course. The philosopher Confucius is buried on the north bank of the Si River where it passes through Qufu City. The river was also traditionally regarded as a place where the Nine Cauldrons were lost. Si River The Si River is a river in Shandong Province, China. It also ran through the area of modern Jiangsu Province until floods in 1194. The Si rises in the southern foothills of the Mengshan Mountains (蒙山),