Karen Leung Worksheet 7 Kinetics Part 1, #5 [ENDORSED]

$aR \to bP, Rate = -\frac{1}{a} \frac{d[R]}{dt} = \frac{1}{b}\frac{d[P]}{dt}$

Sabrina Dunbar 1I
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Karen Leung Worksheet 7 Kinetics Part 1, #5

HI, when we are given a table of values like the one given in Karen Leung's Worksheet 7 titled Kinetics Part 1, how to we incorporate coefficients from the chemical reaction equation into our calculations? The equation given is 2A+B+3C=2D+F. The table given is the same as others we have seen in the past. I calculated A to be 1st order, B to be 2nd order and C to be 0 order. However, the rate law given as the solution is rate=k[A][B]^1/2. Any guidance on this would be much appreciated!
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Re: Karen Leung Worksheet 7 Kinetics Part 1, #5  [ENDORSED]

The order with respect to B should actually be 1/2 not 2. If you divide experiment 4 by experiment 3, then you get 4^x = 2. Therefore, the order is 1/2 not 2. Your answers for orders of A and C are correct. In problems like this, the coefficients of the balanced chemical equation don't come into play unless somehow you are asked to determine a unique rate or are given rate information in terms of multiple reactants that you will need to convert in terms of the unique rate or all in terms of the same reactant for comparison.

Here all rates are given in terms of the unique rate so no need to convert.