I'm still confused about how to identify the order of a reactant. For example, how do we identify the order of reactants, A, B, and C in the following reaction?
2A(g)+2B(g)+C(g)⟶3G(g)+4F(g)
Order of Reactants
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Re: Order of Reactants
If this is an elementary step, then the order of the reaction is determined by molecularity and would be second order with respect to A and B and first order with respect to C.
But I think the order of a non-elementary reaction has to be experimentally determined, meaning only with a data table and finding out how the rate of the overall reaction changes with the concentration of specific reactants can we determine the order of each reactant and the overall reaction.
But I think the order of a non-elementary reaction has to be experimentally determined, meaning only with a data table and finding out how the rate of the overall reaction changes with the concentration of specific reactants can we determine the order of each reactant and the overall reaction.
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Re: Order of Reactants
Are you missing some information. Usually, you can only use the data table to see how the concentrations and the rate of the species are "changing" over time?
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Re: Order of Reactants
If this is from Sapling question 7, then you have to use the data provided to find the orders. You can write out the rate law (leaving the exponents as variables) for two different experiments and divide them to solve for those variables.
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Re: Order of Reactants
If you are given elementary steps, then the orders are determined by the coefficients. However, if you are not given elementary steps, then you need to find the experimentally determined rate law from a table of values. This table of values includes concentrations of reactants and the specific rate at those concentrations. Using these numbers, you can determine the order of each reactant and, eventually, the rate constant.
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Re: Order of Reactants
You can't determine the order just by the chemical equation, so that would be an indicator that you'd need more information!
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Re: Order of Reactants
Given a formula alone, it is impossible to determine the order of reactants. You must be given a table complete with experiments that allow you to see see what increasing the concentration of only one of reactants does to the amount of product.
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