| 释义 |
van't Hoff equation
van't Hoff equation[van′tȯf i‚kwā·zhən] (physical chemistry) An equation for the variation with temperature T of the equilibrium constant K of a gaseous reaction in terms of the heat of reaction at constant pressure, Δ H: d (ln K)/ dT = Δ H/RT 2, where R is the gas constant. Also known as van't Hoff isochore. van't Hoff equation
van't Hoff e·qua·tion (vahnt hof), 1. equation for osmotic pressure of dilute solutions. 2. for any reaction, d(ln Keq)/d(1/T) equals -ΔH/R where Keq is the equilibrium constant, T the absolute temperature, R the universal gas constant, and ΔH the change in enthalpy; thus, plotting ln Keq vs. 1/T allows the determination of ΔHo and ΔSo, where ΔHo and ΔSo are the standard changes in enthalpy and entropy, respectively. [Jacobus H. van't Hoff] van't Hoff e·qua·tion (vahnt hof ĕ-kwā'zhŭn) 1. Calculation for osmotic pressure of dilute solutions.
See also: van't Hoff law2. For any reaction, d(ln Keq/d(1/T) equals -ΔH/R,where Keq is the equilibrium constant, T the absolute temperature, R the universal gas constant, and ΔH the change in enthalpy; thus, plotting ln Keqvs. 1/T allows the determination of ΔH. [Jacobus H. van't Hoff]van't Hoff, Jacobus H., Dutch chemist and Nobel laureate, 1852-1911. Le Bel-van-t Hoff rule - see under Le Belvan't Hoff equation - equation for osmotic pressure of dilute solutions for any reaction.van't Hoff law - in stereochemistry, all optically active substances have one or more multivalent atoms united to four different atoms or radicals so as to form in space an unsymmetrical arrangement.van't Hoff theory - that substances in dilute solution obey the gas laws. |