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where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...
These reactions frequently have a pressure and temperature dependence region of transition between second and third order kinetics. [ 8 ] Catalytic reactions are often three-component, but in practice a complex of the starting materials is first formed and the rate-determining step is the reaction of this complex into products, not an ...
RNA folding problem: Is it possible to accurately predict the secondary, tertiary and quaternary structure of a polyribonucleic acid sequence based on its sequence and environment? Protein design : Is it possible to design highly active enzymes de novo for any desired reaction?
The classical Stefan problem aims to describe the evolution of the boundary between two phases of a material undergoing a phase change, for example the melting of a solid, such as ice to water. This is accomplished by solving heat equations in both regions, subject to given boundary and initial conditions.
The fractional extent of the reaction (i.e. the percentage change in concentration of a measurable species) depends on the molar enthalpy change (ΔH°) between the reactants and products and the equilibrium position. If K is the equilibrium constant and dT is the change in temperature then the enthalpy change is given by the Van 't Hoff equation:
In outer sphere redox reactions no bonds are formed or broken; only an electron transfer (ET) takes place. A quite simple example is the Fe 2+ /Fe 3+ redox reaction, the self exchange reaction which is known to be always occurring in an aqueous solution containing the aquo complexes [Fe(H 2 O) 6] 2+ and [Fe(H 2 O)6] 3+.
A reaction can also have an undefined reaction order with respect to a reactant if the rate is not simply proportional to some power of the concentration of that reactant; for example, one cannot talk about reaction order in the rate equation for a bimolecular reaction between adsorbed molecules:
The reaction of quadricyclane with DEAD is a 2σ + 2σ + 2π cycloaddition that on water takes place within 10 minutes at room temperature with 82% yield. The same reaction in toluene takes 24 hours at 80 °C with 70% yield. An emulsion reaction in fluorinated cyclohexane takes 36 hours and the neat reaction takes even longer (48 hours).