   Chapter 12, Problem 78AE

Chapter
Section
Textbook Problem

# The decomposition of NH3 to N2 and H2 was studied on two surfaces: Surface Ea (kJ/mol) W 163 Os 197 Without a catalyst, the activation energy is 335 kJ/mol.a. Which surface is the better heterogeneous catalyst for the decomposition of NH3? Why?b. How many times faster is the reaction at 298 K on the W surface compared with the reaction with no catalyst present? Assume that the frequency factor A is the same for each reaction.c. The decomposition reaction on the two surfaces obeys a rate law of the form Rate   =   k [ NH 3 ] [ H 2 ] How can you explain the inverse dependence of the rate on the H2 concentration?

(a)

Interpretation Introduction

Interpretation: The activation energy of decomposition reaction of NH3 without and with catalyst is given. Based on these data answers are to be given.

Concept introduction: The substance that speeds up the rate of reaction without getting consumed itself in a chemical reaction is known as catalyst.

The relationship between the rate constant and temperature is given by the Arrhenius equation,

k=AeEaRT

To determine: The surface that is better heterogeneous catalyst for the decomposition of NH3 with proper explanation.

Explanation

Given

The activation energy with catalyst surface of W is 163kJ/mol .

The activation energy with catalyst surface of Os is 197kJ/mol .

The activation energy without catalyst surface is 335kJ/mol

(b)

Interpretation Introduction

Interpretation: The activation energy of decomposition reaction of NH3 without and with catalyst is given. Based on these data answers are to be given.

Concept introduction: The substance that speeds up the rate of reaction without getting consumed itself in a chemical reaction is known as catalyst.

The relationship between the rate constant and temperature is given by the Arrhenius equation,

k=AeEaRT

To determine: The comparison of rate of reaction with catalyst W and with no catalyst at 298K .

(c)

Interpretation Introduction

Interpretation: The activation energy of decomposition reaction of NH3 without and with catalyst is given. Based on these data answers are to be given.

Concept introduction: The substance that speeds up the rate of reaction without getting consumed itself in a chemical reaction is known as catalyst.

The relationship between the rate constant and temperature is given by the Arrhenius equation,

k=AeEaRT

To determine: The explanation that the rate of reaction is inversely dependent on the H2 concentration.

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started 