± Half-life (kinetics) for First Order Reactions < 10 of 18> I Review | Constants | Periodic Table Half-life equation for first-order reactions: The integrated rate law allows chemists to predict the reactant concentration after a certain amount of time, or the time it would take for a certain concentration to be 0.693 reached. where t2 is the half-life in seconds (s), and k is the rate constant inverse seconds (s1) The integrated rate law for a first-order reaction is: [A] = [A]oe Part A Now say we are particularly interested in the time it would take for the concentration to become one-half of its initial JA What is the half-life of a first-order reaction with a rate constant of 7.40x10-4 s12 value. Then we could substitute for [A] and rearrange the equation to: Express your answer with the appropriate units. > View Available Hint(s) 4/2 = 0.603 This equation calculates the time required for the reactant concentration to drop to half its initial value. In other words, it calculates the half-life, ? Value Units

± Half-life (kinetics) for First Order Reactions < 10 of 18> I Review | Constants | Periodic Table Half-life equation for first-order reactions: The integrated rate law allows chemists to predict the reactant concentration after a certain amount of time, or the time it would take for a certain concentration to be 0.693 reached. where t2 is the half-life in seconds (s), and k is the rate constant inverse seconds (s1) The integrated rate law for a first-order reaction is: [A] = [A]oe Part A Now say we are particularly interested in the time it would take for the concentration to become one-half of its initial JA What is the half-life of a first-order reaction with a rate constant of 7.40x10-4 s12 value. Then we could substitute for [A] and rearrange the equation to: Express your answer with the appropriate units. > View Available Hint(s) 4/2 = 0.603 This equation calculates the time required for the reactant concentration to drop to half its initial value. In other words, it calculates the half-life, ? Value Units

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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The decomposition of N2O5 in solution in carbon tetrachloride is a first-order reaction. 2N2O5 → 4NO2 + O2 The rate constant at a given temperature is found to be 5.25 x 10-4 s-1. If the initial concentration of N2O5 is 0.24 M, what is its concentration after exactly 9 minutes have passed? Round your answer to 2 decimal places
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