# test1s - 3. The rate equations are A and B are reactants, C...

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Up: Back to the Chemistry 2000 test index Chemistry 2000, Fall 96, Test 1 Solutions 1. From the last two lines of the table, we see that increasing [B] has no effect on the rate. Therefore, the reaction is zero-order with respect to B so we can ignore this concentration altogether. From the first two lines, we see that doubling [A] doubles the rate so the reaction is first-order with respect to A. The rate equation is therefore The rate constant can be obtained from (say) the first line of the table using the rate law: 2. We want to know how long it takes before . The first-order equation can be rewritten k is computed from the half-life: (I believe that the true detection limits are somewhat lower so that the carbon dating method can be used to determine dates of samples somewhat older than this calculation shows.)

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Unformatted text preview: 3. The rate equations are A and B are reactants, C is an intermediate and P is a product. 4. Using the first piece of data and the Arrhenius equation, we have The second data point gives us Subtract the two equations to eliminate : Now substitute this data back into one of the two original equations, say the first one: 1. The half-life is the time required for half the original quantity of a reactant to be removed. 2. At , . Substituting these values into the third-order equation, we have 3. The rate constant for a third-order process is in . 4. If we plot as a function of time, we get a straight line of slope 2 k . The rate constant is therefore extracted by dividing the slope of the plot by 2. Marc Roussel Thu Sep 26 13:13:23 MDT 1996...
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## This note was uploaded on 03/03/2012 for the course CHEM 2000 taught by Professor Roussel during the Fall '06 term at Lethbridge College.

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test1s - 3. The rate equations are A and B are reactants, C...

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