Phase inversion (chemistry) Phase inversion (chemistry) Phase inversion is a chemical phenomenon exploited in the fabrication of artificial membranes. It is performed by removing the solvent from a liquid-polymer solution, leaving a porous, solid membrane. Phase inversion is a common method to form filtration membranes, which are typically formed using artificial polymers. The method of phase inversion is highly dependent on the type of polymer used and the solvent used to dissolve the polymer. Phase inversion can be carried out through one of four typical methods: The rate at which phase inversion occurs and the characteristics of the resulting membrane are dependent on
Equivalent (chemistry) Equivalent (chemistry) An equivalent (symbol: equiv) is the amount of a substance that reacts with (or is "equivalent" to) an arbitrary amount of another substance in a given chemical reaction. It is an archaic unit of measurement that was used in chemistry and the biological sciences in the era before researchers knew how to determine the chemical formula for a compound. The mass of an equivalent is called its equivalent weight. In a more formal definition, the "equivalent" is the amount of a substance needed to do one of the following: By this definition, an "equivalent" is the number of