Solve for desired concentration of part needed in

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solve for desired concentration of part needed in rate law (eliminating the intermediate) combine all forms of “k” into one K 15.7 steady state approximation cases in which a specific rate determining step cannot be chosen assume concentrations of any intermediates remain constant assume rate of production=total rate of consumption rate of production=reverse rate of production + rate of consumption solve for the concentration desired and substitute into rate law an intermediate is neither a reactant nor a product but something that is formed and  then consumed as the reaction proceeds analyzing a mechanism using the steady-state approximation
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03:14 write the proposed mechanism (elementary steps0 construct a steady state expression for each intermediate I by applying the criterion d[I]/dt=0 rate of production=rate of consumption of I solve for [I]2 [I]3 etc construct rate law for overall reaction in terms of one of the reactants or products based  on convenience substitute and solve 15.8 model for chemical kinetics collision model- built around the central idea that molecules must collide to react only a small portion of molecules produce a collision threshold energy (activation energy) must be overcome to produce a chemical reaction the higher the activation energy, the slower the reaction at a given temp on a activiation energy graph x axis reactants products y axis potential energy before Ea hump is Ea(fwd) after Ea hump is Ea(rev) k=Ae^(-Ea/RT) at high temperature, it is a fast reaction experiments show that the observed reaction rate is considerably smaller than the rate  of collisions with enough energy to surmount the barrier to collide successfully
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03:14 involve enough energy to produce the reaction, equal or exceed activation energy relative orientations of the reactants must allow formation of any new bonds necessary  to produce products ln(k2/k1)=Ea/R[(1/T1)-(1/T2)] 15.9 catalysis the use of catalysts to speed up reactions without changing the temperature catalyst- substance that speeds up a reaction without being consumed by the reaction homogeneous catalyst- same phase as reacting molecules heterogeneous catalysts- different phase from the reacting molecules enhance reaction rates by many orders of magnitude; LOWER the Ea graph of catalysis x axis reactants products y axis E Ea(fwd)(uncat) is height from start to top of uncatalyzed pathway Ea(fwd)(cat) is height from start to top of catalyzed pathway Ea(rev)(cat) is height from top of catalyzed pathway to end Ea(rev)(uncat) is height from top of uncatalyzed pathway to end Edelta is height between start and finish
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