Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 14: Problem 75

Briefly comment on the effect of a catalyst on each of the following: (a) activation energy, (b) reaction mechanism, (c) enthalpy of reaction, (d) rate of forward step, (e) rate of reverse step.

Short Answer

Expert verified
A catalyst decreases the activation energy, changes the reaction mechanism, has no effect on enthalpy, and increases both the rate of the forward and reverse steps.

Step by step solution

01

Implication of a Catalyst on Activation Energy

A catalyst provides an alternate path or mechanism for a reaction to follow, which has a lower activation energy than the uncatalyzed reaction. Therefore, a catalyst decreases the activation energy of a reaction.
02

Implication of a Catalyst on Reaction Mechanism

A catalyst doesn't change the reaction itself but provides a new mechanism or reaction path to proceed, that is, it changes the intermediary stages of the reaction while the initial and final stages remain the same.
03

Implication of a Catalyst on Enthalpy of Reaction

Since a catalyst doesn't change the states of the reactants and products, it has no effect on the enthalpy or heat content of the reaction. The enthalpy change (\( \Delta H\)) for a reaction remains the same whether a catalyst is used or not.
04

Implication of a Catalyst on Rate of Forward Step

By lowering the activation energy, a catalyst increases the rate of the forward step of a reaction, so the reaction reaches equilibrium more quickly.
05

Implication of a Catalyst on Rate of Reverse Step

A catalyst accelerates both the forward and reverse reactions equally, because it merely lowers the activation energy barrier. So, the rate of reverse reaction also increases when a catalyst is involved.

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

For the reaction $$ \mathrm{NO}(g)+\mathrm{O}_{3}(g) \longrightarrow \mathrm{NO}_{2}(g)+\mathrm{O}_{2}(g) $$ the frequency factor \(A\) is \(8.7 \times 10^{12} \mathrm{~s}^{-1}\) and the activation energy is \(63 \mathrm{~kJ} / \mathrm{mol}\). What is the rate constant for the reaction at \(75^{\circ} \mathrm{C} ?\)

Consider the following elementary steps for a consecutive reaction $$ \mathrm{A} \stackrel{k_{1}}{\longrightarrow} \mathrm{B} \stackrel{k_{2}}{\longrightarrow} \mathrm{C} $$ (a) Write an expression for the rate of change of \(\mathrm{B}\). (b) Derive an expression for the concentration of \(\mathrm{B}\) under steady- state conditions; that is, when \(\mathrm{B}\) is decomposing to \(\mathrm{C}\) at the same rate as it is formed from \(\mathrm{A}\).

What are the characteristics of a catalyst?

Distinguish between homogeneous catalysis and heterogeneous catalysis. Describe some important industrial processes that utilize heterogeneous catalysis.

Consider the reaction $$ X+Y \longrightarrow Z $$ These data are obtained at \(360 \mathrm{~K}\): $$ \begin{aligned} &\text { Initial Rate of }\\\ &\begin{array}{ccc} \text { Disappearance of } \mathrm{X}(\mathrm{M} / \mathrm{s}) & {[\mathrm{X}]} & {[\mathrm{Y}]} \\ \hline 0.147 & 0.10 & 0.50 \\ 0.127 & 0.20 & 0.30 \\ 4.064 & 0.40 & 0.60 \\ 1.016 & 0.20 & 0.60 \\ 0.508 & 0.40 & 0.30 \end{array} \end{aligned} $$ (a) Determine the order of the reaction. (b) Determine the initial rate of disappearance of \(X\) when the concentration of \(\mathrm{X}\) is \(0.30 \mathrm{M}\) and that of \(\mathrm{Y}\) is \(0.40 \mathrm{M}\)
See all solutions

Recommended explanations on Chemistry Textbooks

Making Measurements

Read Explanation

Organic Chemistry

Read Explanation

Kinetics

Read Explanation

The Earths Atmosphere

Read Explanation

Nuclear Chemistry

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