Introduction to electromagnetism is a quantity used to determine how a particle will behave in an electric field. There are three possible "types" of charge: positive, negative, and neutral. However, the distinction between positive and negative is by convention only. Electric charge is quantized in units of the elementary charge, formula_1, where a proton has a charge of formula_2 and an electron has a charge of formula_3. The SI unit of charge is the coulomb. The elementary charge formula_1 was first measured by Robert Millikan in his oil drop experiment in which the electric force on the particle is set to exactly counter
Point of zero charge Point of zero charge The point of zero charge (pzc), in physical chemistry, is a concept relating to the phenomenon of adsorption, and it describes the condition when the electrical charge density on a surface is zero. It is usually determined in relation to an electrolyte's pH, and the pzc value is assigned to a given substrate or colloidal particle. For example, the pzc of solid FeOOH is 9. In other words, pzc is (usually) the pH value at which a solid submerged in an electrolyte exhibits zero net electrical charge on the surface. A related concept in electrochemistry is