The half-life of a reaction, £₁/2, is the time it takes for the reactant concentration [A] todecrease by half. For example, after one half-life the concentration falls from the initialconcentration [A]o to [A]o/2, after a second half-life to [A]o/4, after a third half-lifeto [Ale/8, and so on. on.For a first-order reaction, the half-life is constant. It depends only on the rate constant k and not on the reactant concentration. It is expressed asIn(2)t1/2 =kFor a second-order reaction, the half-life depends on the rate constant and the concentration of the reactant and so is expressed asPart A1A certain first-order reaction (A-products) has a rate constant of 6.30x10 s¹ at 45 °C. How long does it take for the concentration of the reactant, [A], to drop to 6.25% of the original concentration?Express your answer with the appropriate units.▸ View Available Hint(s)CHValueSubmitμA▾ Part BHA 1Ċ 13ValueUnitsA certain second-order reaction (B-products) has a rate constant of 1.35x10-3 M-¹.s¹ at 27 °C and an initial half-life of 240 s. What is the concentration of the reactant B after one half-life?Express your answer with the appropriate units.▸ View Available Hint(s)t₁/2 =k[A]o=-1E ?Units

Given question is related to the rate equation of first order and second order reactions.

half-life of a reaction, f/2, is the time it takes for the reactant concentration Alto ase by half. For example, after one half-life the concentration falls from the initial entration (Ale to (Ala/2. after a second half-life to Alo/4. after a third half-life -lo/8, and so on. on. For a first-order reaction, the half-life is constant. It depends only on the rate constant it and not on the reactant concentration. It is expressed as 1/2 - 1(2) For a second-order reaction, the half-life depends on the rate constant and the concentration of the reactant and so is expressed as t1/2 =Ala Part A A certain first-order reaction (A ->products) has a rate constant of 6.30x10 s at 45 °C. How long does it take for the concentration of the reactant. (A), to drop to 6.25% of the original concentration? Express your answer with the appropriate units. ▸ View Available Hint(s) Submit Value Part B. HA ▸ View Available Hint(s) → A certain second-order reaction (B products) has a rate constant of 1.35x10 Ms at 27 °C and an initial half-life of 240 s. What is the concentration of the reactant B after one half-life? Express your answer with the appropriate units. 4 I ? Units CIF ?

half-life of a reaction, f/2, is the time it takes for the reactant concentration Alto ase by half. For example, after one half-life the concentration falls from the initial entration (Ale to (Ala/2. after a second half-life to Alo/4. after a third half-life -lo/8, and so on. on. For a first-order reaction, the half-life is constant. It depends only on the rate constant it and not on the reactant concentration. It is expressed as 1/2 - 1(2) For a second-order reaction, the half-life depends on the rate constant and the concentration of the reactant and so is expressed as t1/2 =Ala Part A A certain first-order reaction (A ->products) has a rate constant of 6.30x10 s at 45 °C. How long does it take for the concentration of the reactant. (A), to drop to 6.25% of the original concentration? Express your answer with the appropriate units. ▸ View Available Hint(s) Submit Value Part B. HA ▸ View Available Hint(s) → A certain second-order reaction (B products) has a rate constant of 1.35x10 Ms at 27 °C and an initial half-life of 240 s. What is the concentration of the reactant B after one half-life? Express your answer with the appropriate units. 4 I ? Units CIF ?

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter13: Chemical Kinetics

Section: Chapter Questions

Problem 13.50QE

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Define stability from both a kinetic and thermodynamic perspective. Give examples to show the differences in these concepts.
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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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