Which of the following linear plots do you expect for a reaction \(A \longrightarrow\) products if the kinetics are (a) zero order, (b) first order, or (c) second order? [Section 14.4\(]\)

Short Answer

Expert verified
For (a) zero-order, (b) first-order, and (c) second-order kinetics, the linear plots are: a) \( [A] \) vs. \( t \), with a straight line and a negative slope equal to \( -k \) b) \( ln[A] \) vs. \( t \), with a straight line and a negative slope equal to \( -k \) c) \( \frac{1}{[A]} \) vs. \( t \), with a straight line and a positive slope equal to \( k \)

Step by step solution

01

Review the mathematical expressions for each type of kinetics

First, let's review the mathematical expressions for each type of kinetics. 1. Zero-order kinetics: The reaction rate is constant. The rate equation is: \[r = k[A]^0 = k\] 2. First-order kinetics: The reaction rate is proportional to the concentration of the single reactant A. The rate equation is: \[r = k[A]\] 3. Second-order kinetics: The reaction rate is proportional to the square of the concentration of the single reactant A. The rate equation is: \[r = k[A]^2\] Now that we have the rate equations for each type of kinetics, we can proceed to determine their linear plots.
02

Identify the linear plots for each type of kinetics

We will now find the linear plots for each type of kinetics by integrating the corresponding rate equations and looking for linear relationships. 1. Zero-order kinetics: For a zero-order reaction, after integrating the rate equation, we get: \[[A] = -kt + [A]_0\] This equation represents a linear plot; the concentration [A] decreases linearly with time t. Thus, a graph of [A] vs. t gives a straight line with a negative slope equal to -k. 2. First-order kinetics: For a first-order reaction, after integrating the rate equation, we get: \[ln[A] = -kt + ln[A]_0\] In this case, a linear plot can be achieved by plotting the natural logarithm of the concentration ln[A] vs. time t. This plot gives a straight line with a negative slope equal to -k. 3. Second-order kinetics: For a second-order reaction, after integrating the rate equation, we get: \[\frac{1}{[A]} = kt + \frac{1}{[A]_0}\] Here, a linear plot can be obtained by plotting the reciprocal of the concentration 1/[A] vs. time t. This plot results in a straight line with a positive slope equal to k. In summary, for reactions with (a) zero-order, (b) first-order, and (c) second-order kinetics, the expected linear plots are: a) [A] vs. t, with a straight line and a negative slope equal to -k b) ln[A] vs. t, with a straight line and a negative slope equal to -k c) 1/[A] vs. t, with a straight line and a positive slope equal to k

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

(a) The reaction \(\mathrm{H}_{2} \mathrm{O}_{2}(a q) \longrightarrow \mathrm{H}_{2} \mathrm{O}(l)+\frac{1}{2} \mathrm{O}_{2}(g)\) is first order. At 300 \(\mathrm{K}\) the rate constant equals \(7.0 \times 10^{-4} \mathrm{s}^{-1}\) . Calculate the half-life at this temperature. (b) If the activation energy for this reaction is \(75 \mathrm{kJ} / \mathrm{mol},\) at what temperature would the reaction rate be doubled?

For the elementary process \(\mathrm{N}_{2} \mathrm{O}_{5}(g) \longrightarrow \mathrm{NO}_{2}(g)+\mathrm{NO}_{3}(g)\) the activation energy \(\left(E_{a}\right)\) and overall \(\Delta E\) are 154 \(\mathrm{kJ} / \mathrm{mol}\) and 136 \(\mathrm{kJ} / \mathrm{mol}\) , respectively. (a) Sketch the energy profile for this reaction, and label \(E_{a}\) and \(\Delta E\) . (b) What is the activation energy for the reverse reaction?

For each of the following gas-phase reactions, indicate how the rate of disappearance of each reactant is related to the rate of appearance of each product: \(\begin{array}{l}{\text { (a) } \mathrm{H}_{2} \mathrm{O}_{2}(g) \longrightarrow \mathrm{H}_{2}(g)+\mathrm{O}_{2}(g)} \\ {\text { (b) } 2 \mathrm{N}_{2} \mathrm{O}(g) \longrightarrow 2 \mathrm{N}_{2}(g)+\mathrm{O}_{2}(g)} \\ {\text { (c) } \mathrm{N}_{2}(g)+3 \mathrm{H}_{2}(g) \longrightarrow 2 \mathrm{NH}_{3}(g)} \\ {\text { (d) } \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}(g) \longrightarrow \mathrm{C}_{2} \mathrm{H}_{4}(g)+\mathrm{NH}_{3}(g)}\end{array}\)

Enzymes are often described as following the two-step mechanism: $$ \begin{array}{c}{\mathrm{E}+\mathrm{S} \rightleftharpoons \mathrm{ES} \text { (fast) }} \\ {\mathrm{ES} \longrightarrow \mathrm{E}+\mathrm{P} \quad(\text { slow })}\end{array}$$ where \(\mathrm{E}=\) enzyme, \(\mathrm{S}=\) substrate,\(\mathrm{ES}=\) enzyme-substrate complex, and \(\mathrm{P}=\) product.(a) If an enzyme follows this mechanism, what rate law is expected for the reaction? (b) Molecules that can bind to the active site of an enzyme but are not converted into product are called enzyme inhibitors. Write an additional elementary step to add into the preceding mechanism to account for the reaction of E with I, an inhibitor.

Indicate whether each statement is true or false. \(\begin{array}{l}{\text { (a) If you measure the rate constant for a reaction at different}} \\ {\text { temperatures, you can calculate the overall }} \\ {\text { enthalpy change for the reaction. }} \\ {\text { (b) Exothermic reactions are faster than endothermic }} \\ {\text { reactions. }} \\ {\text { (c) If you double the temperature for a reaction, you cut }} \\ {\text { the activation energy in half. }}\end{array}\)

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free