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Collision theory is a theory proposed independently by Max Trautz in 1916〔Trautz, Max. ''Das Gesetz der Reaktionsgeschwindigkeit und der Gleichgewichte in Gasen. Bestätigung der Additivität von Cv-3/2R. Neue Bestimmung der Integrationskonstanten und der Moleküldurchmesser'', Zeitschrift für anorganische und allgemeine Chemie, Volume 96, Issue 1, Pages 1 - 28, 1916, ()〕 and William Lewis in 1918, that qualitatively explains how chemical reactions occur and why reaction rates differ for different reactions. The collision theory states that when suitable particles of the reactant hit each other, only a certain percentage of the collisions cause any noticeable or significant chemical change; these successful changes are called successful collisions. The successful collisions have enough energy, also known as activation energy, at the moment of impact to break the preexisting bonds and form all new bonds. This results in the products of the reaction. Increasing the concentration of the reactant particles or raising the temperature, thus bringing about more collisions and therefore many more successful collisions, increases the rate of reaction. When a catalyst is involved in the collision between the reactant molecules, less energy is required for the chemical change to take place, and hence more collisions have sufficient energy for reaction to occur. The reaction rate therefore increases. Collision theory is closely related to chemical kinetics. ==Rate constant== The rate constant for a bimolecular gas phase reaction, as predicted by collision theory is: :. where: *''Z'' is the collision frequency. * is the steric factor. *''Ea'' is the activation energy of the reaction. *''T'' is the temperature. *''R'' is the gas constant. The collision frequency is: : where: *''NA'' is the Avogadro constant *''σAB'' is the reaction cross section *''kB'' is the Boltzmann's constant *''μAB'' is the reduced mass of the reactants. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「collision theory」の詳細全文を読む スポンサード リンク
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