▼ What is the half-life of a first-order reaction with a rate constant of 6.70x10-4 S-1? Express your answer with the appropriate units. Value Submit Part B HA Submit Value Part C What is the rate constant of a first-order reaction that takes 490 seconds for the reactant concentration to drop to half of its initial value? Express your answer with the appropriate units. View Available Hint(s) Units Request Answer μA ? Units ? A certain first-order reaction has a rate constant of 9.00x10-3 s¹. How long will it take for the reactant concentration to drop to of its initial value? Express your answer with the appropriate units. 87

▼ What is the half-life of a first-order reaction with a rate constant of 6.70x10-4 S-1? Express your answer with the appropriate units. Value Submit Part B HA Submit Value Part C What is the rate constant of a first-order reaction that takes 490 seconds for the reactant concentration to drop to half of its initial value? Express your answer with the appropriate units. View Available Hint(s) Units Request Answer μA ? Units ? A certain first-order reaction has a rate constant of 9.00x10-3 s¹. How long will it take for the reactant concentration to drop to of its initial value? Express your answer with the appropriate units. 87

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter11: Chemical Kinetics: Rates Of Reactions

Section: Chapter Questions

Problem 112QRT

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The rate of the reaction O(g)+NO2(g)NO(g)+O2(g) was studied at a certain temperature. a. In one experiment, NO2 was in large excess, at a concentration of 1.0 1013 molecules/cm3 with the following data collected: Time(s) [O](atoms/cm3) 0 5.0 109 1.0 102 1.9 109 2.0 102 6.8 108 3.0 102 2.5 108 What is the order of the reaction with respect to oxygen atoms? b. The reaction is known to be first order with respect to NO2 Determine the overall rate law and the value of the rate constant.
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Regular ?ights of supersonic aircraft in the stratosphere ale of concern because such aircraft produce nitric oxide, NO, as a byproduct in the exhaust of their engines. Nitric oxide reacts with ozone, and it has been suggested that this could contribute to depletion of the ozone layer. The reaction NO+O3NO2+O2 is first order with respect to both NO and O3 with a rate constant of 2.20107 L/mol/s. What is the instantaneous rate of disappearance of NO when [NO]=3.3106 M and [O3]=5.9107M?
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