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In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base.It can be used to determine pH via titration.Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.
The reaction rate varies depending upon what substances are reacting. Acid/base reactions, the formation of salts, and ion exchange are usually fast reactions. When covalent bond formation takes place between the molecules and when large molecules are formed, the reactions tend to be slower.
The model was later expanded to the ECW model to cover reactions that have a constant energy term, W, which describes processes that precede the acid–base reaction. This quantitative model is often discussed with the qualitative HSAB theory, which also seeks to rationalize the behavior of diverse acids and bases.
Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. The study of how fast an enzyme can transform a substrate into a product is called enzyme kinetics. The rate of reaction of many chemical reactions shows a linear response as function of the concentration of substrate molecules.
For the NO 2 –CO reaction above, the rate depends on [NO 2] 2, so that the activated complex has composition N 2 O 4, with 2 NO 2 entering the reaction before the transition state, and CO reacting after the transition state. A multistep example is the reaction between oxalic acid and chlorine in aqueous solution: H 2 C 2 O 4 + Cl 2 → 2 CO 2 ...
Chemical decomposition, or chemical breakdown, is the process or effect of simplifying a single chemical entity (normal molecule, reaction intermediate, etc.) into two or more fragments. [1] Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis .
The laminar finite rate model computes the chemical source terms using the Arrhenius expressions and ignores turbulence fluctuations. This model provides with the exact solution for laminar flames but gives inaccurate solution for turbulent flames, in which turbulence highly affects the chemistry reaction rates, due to highly non-linear Arrhenius chemical kinetics.
Since the reaction rate determines the reaction timescale, the exact formula for the Damköhler number varies according to the rate law equation. For a general chemical reaction A → B following the Power law kinetics of n-th order, the Damköhler number for a convective flow system is defined as: