Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 13: Problem 120

The mechanism for the reaction of \(A_{2}\) with \(B\) is: Step \(1: \mathrm{A}_{2}+\mathrm{Y} \rightarrow \mathrm{AY}+\mathrm{A}\) (slow) Step \(2: \mathrm{A}+\mathrm{B} \rightarrow \mathrm{AB}\) (fast) Step 3: \(\mathrm{AY}+\mathrm{AB} \rightarrow \mathrm{Y}+\mathrm{A}_{2} \mathrm{~B}\) (fast) (a) Write the overall reaction that is occurring. (b) Which step determines the rate law for the reaction? (c) Write the rate law for the reaction. (d) What happens to the rate of the reaction when \(\left[\mathrm{A}_{2}\right]\) is doubled? (e) Which species is the catalyst? (f) Which species are reaction intermediates?

Short Answer

Expert verified
(a) The overall reaction is \(A_2 + B \rightarrow A_2B\). (b) The rate-determining step is Step 1. (c) The rate law is Rate = \(k[\mathrm{A}_{2}][\mathrm{Y}]\). (d) Doubling \([\mathrm{A}_{2}]\) will double the reaction rate. (e) The catalyst is Y. (f) The reaction intermediates are A and AY.

Step by step solution

01

(a) Overall Reaction Equation

To find the overall reaction equation, we'll add the given elementary steps and then cancel out any common species on both sides of the reaction: Step 1: \(A_2 + Y \rightarrow AY + A\) (slow) Step 2: \(A + B \rightarrow AB\) (fast) Step 3: \(AY + AB \rightarrow Y + A_2B\) (fast) Adding the steps: \( A_2 + Y + A + B \rightarrow AY + A + AB + Y + A_2B \) Cancel out common species: \( Y, A \) Resulting overall reaction: \( A_2 + B \rightarrow A_2B \)
02

(b) Rate-Determining Step

The rate-determining step is the slowest step in the mechanism. In this case, it is Step 1, where \( A_2 + Y \rightarrow AY + A\).
03

(c) Rate Law

The rate law is determined by the rate-determining step in the mechanism: Rate = \(k[\mathrm{A}_{2}][\mathrm{Y}]\)
04

(d) Effect of Doubling \([\mathrm{A}_{2}]\) on Reaction Rate

When the concentration of A₂ is doubled, the rate will also double since the rate law is directly proportional to the concentration \([\mathrm{A}_{2}] \): New rate = \(k[2 \times \mathrm{A}_{2}][\mathrm{Y}]\) = \(2k[\mathrm{A}_{2}][\mathrm{Y}]\)
05

(e) Catalyst

A catalyst is a species that participates in the reaction mechanism but is regenerated by the end of the mechanism. In this case, Y is the catalyst as it is consumed in the first step and regenerated in the last step.
06

(f) Reaction Intermediates

Reaction intermediates are species that are both formed and consumed within the reaction mechanism. In this case, A and AY are intermediates as they are formed in the first step and consumed in the second and third steps, respectively.

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.

Start your free trial

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 reaction \(\mathrm{A}+\mathrm{B} \rightarrow\) Product is run in a balloon. (Both A and B are gases.) The balloon has a volume of 1 L and is initially loaded with 1 mole of \(\mathrm{A}\) and \(1 \mathrm{~mole}\) of \(\mathrm{B}\). The reaction has the rate law Rate \(=k[\mathrm{~A}]\) The reaction is run again using the same amount of reactants, but this time in a balloon that has a volume of \(0.5 \mathrm{~L}\). How much faster will the reaction proceed in the smaller balloon? Explain your answer.

Which reaction occurs fastest, one with \(E_{\mathrm{a}}=20 \mathrm{~kJ}\), one with \(E_{\mathrm{a}}=50 \mathrm{~kJ}\), or one with \(E_{\mathrm{a}}=75 \mathrm{~kJ}\) ?

Does the rate constant \(k\) increase, decrease, or stay the same when: (a) You increase the temperature (explain your choice fully). (b) You add a catalyst (explain your choice fully).

In a chemical reaction, compound A is converted to compound \(\mathrm{B}\). In the process, energy is absorbed from the surroundings. Which compound is at a higher energy level? Explain your answer.

Why can we ignore other steps and use only the rate-determining step in a mechanism to write the predicted rate law?
See all solutions

Recommended explanations on Chemistry Textbooks

The Earths Atmosphere

Read Explanation

Nuclear Chemistry

Read Explanation

Making Measurements

Read Explanation

Chemical Reactions

Read Explanation

Chemical Analysis

Read Explanation

Inorganic Chemistry

Read Explanation
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