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Chapter 18 Notes, part IV. Rate Law Problems. Rate Laws. Earlier we discussed that the rate at which a reaction goes is dependent on the concentration of the reactants. Rate Laws. If the reaction is A a B, then the rate of reaction is dependent on the concentration of A. So: Rate=k[A] a.
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Chapter 18 Notes, part IV Rate Law Problems
Rate Laws • Earlier we discussed that the rate at which a reaction goes is dependent on the concentration of the reactants.
Rate Laws • If the reaction is AaB, then the rate of reaction is dependent on the concentration of A. • So: • Rate=k[A]a
Or, for A + B a C the rate is • Rate=k[A]a[B]b
Rate Laws • Ideally, the superscript “a” and “b” would correspond to the coefficient of A and B, but because of the complex steps that many reactions undergo forming intermediates, this is not usually the case.
Rate Laws • Because of this, the only way to find out the order (exponent) due to each reactant, you have to experiment!
For the reaction H2 + Cl2a2HCl, the following data was collected: [H2] [Cl2] Initial rate 0.30M 0.30M 1.5x102 0.60M 0.30M 3.0x102 0.30M 0.60M 6.0x102 What is the rate expression? What is k?