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Energy profile diagram for kinetic versus thermodynamic product reaction. Thermodynamic reaction control or kinetic reaction control in a chemical reaction can decide the composition in a reaction product mixture when competing pathways lead to different products and the reaction conditions influence the selectivity or stereoselectivity.
A reaction coordinate diagram can also be used to qualitatively illustrate kinetic and thermodynamic control in a reaction. Figure 9:Kinetic and Thermodynamic Control: A. Product B is both the kinetic and thermodynamic product and B. Product A is the kinetic product while B is the thermodynamic product. [4]
A primary kinetic isotope effect (PKIE) may be found when a bond to the isotopically labeled atom is being formed or broken. [3] [4]: 427 Depending on the way a KIE is probed (parallel measurement of rates vs. intermolecular competition vs. intramolecular competition), the observation of a PKIE is indicative of breaking/forming a bond to the isotope at the rate-limiting step, or subsequent ...
The 'rule of thumb' that the rate of chemical reactions doubles for every 10 °C temperature rise is a common misconception. This may have been generalized from the special case of biological systems, where the α (temperature coefficient) is often between 1.5 and 2.5. The kinetics of rapid reactions can be studied with the temperature jump method.
The ideal kinetic resolution is that in which only one enantiomer reacts, i.e. k R >>k S. The selectivity (s) of a kinetic resolution is related to the rate constants of the reaction of the R and S enantiomers, k R and k S respectively, by s=k R /k S, for k R >k S. This selectivity can also be referred to as the relative rates of reaction.
Chemical thermodynamics is the study of the interrelation of heat and work with chemical reactions or with physical changes of state within the confines of the laws of thermodynamics. Chemical thermodynamics involves not only laboratory measurements of various thermodynamic properties, but also the application of mathematical methods to the ...
The FBISE was established under the FBISE Act 1975. [2] It is an autonomous body of working under the Ministry of Federal Education and Professional Training. [3] The official website of FBISE was launched on June 7, 2001, and was inaugurated by Mrs. Zobaida Jalal, the Minister for Education [4] The first-ever online result of FBISE was announced on 18 August 2001. [5]
In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. [1] Colloquially, it may instead refer to kinetic persistence , the shelf-life of a metastable substance or system; that is, the timescale over which it begins to degrade.