# Calculate [OH − ], [H + ], and the pH of 0.40 M solutions of each of the following amines (the K b values are found in Table 13-3). a. aniline b. methylamine

### Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
Publisher: Cengage Learning
ISBN: 9781305079243

Chapter
Section

### Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
Publisher: Cengage Learning
ISBN: 9781305079243
Chapter 13, Problem 98E
Textbook Problem
53 views

## Calculate [OH−], [H+], and the pH of 0.40 M solutions of each of the following amines (the Kb values are found in Table 13-3).a. anilineb. methylamine

(a)

Interpretation Introduction

Interpretation: The pH,[H+] and [OH] of the given amines is to be calculated.

Concept introduction: The pH of a solution is defined as a figure that expresses the acidity of the alkalinity of a given solution.

The pOH of a solution is calculated by the formula, pOH=log[OH]

The sum, pH+pOH=14

At equilibrium, the equilibrium constant expression is expressed by the formula,

Kb=ConcentrationofproductsConcentrationofreactants

To determine: The pH,[H+] and [OH] of C6H5NH2 .

### Explanation of Solution

Explanation

The equilibrium constant expression for the given reaction is,

Kb=[C6H5NH3+][OH][C6H5NH2]

The reaction involved is,

C6H5NH2(aq)+H2O(l)C6H5NH3+(aq)+OH(aq)

At equilibrium, the equilibrium constant expression is expressed by the formula,

Kb=ConcentrationofproductsConcentrationofreactants

Where,

• Kb is the base ionization constant.

The equilibrium constant expression for the given reaction is,

Kb=[C6H5NH3+][OH][C6H5NH2] (1)

The [OH] is 1.23×10-5M_ .

The change in concentration of C6H5NH2 is assumed to be x .

The liquid components do not affect the value of the rate constant.

The ICE table for the stated reaction is,

C6H5NH2(aq)C6H5NH3+(aq)+OH(aq)Inititialconcentration0.4000Changex+x+xEquilibriumconcentration0.40xxx

The equilibrium concentration of [C6H5NH2] is (0.40x)M .

The equilibrium concentration of [C6H5NH3+] is xM .

The equilibrium concentration of [OH] is xM .

The Kb value is given to be 3.8×1010 .

Substitute the value of Kb , [C6H5NH2] , [C6H5NH3+] and [OH] in equation (1)

(b)

Interpretation Introduction

Interpretation: The pH,[H+] and [OH] of the given amines is to be calculated.

Concept introduction: The pH of a solution is defined as a figure that expresses the acidity of the alkalinity of a given solution.

The pOH of a solution is calculated by the formula, pOH=log[OH]

The sum, pH+pOH=14

At equilibrium, the equilibrium constant expression is expressed by the formula,

Kb=ConcentrationofproductsConcentrationofreactants

To determine: The pH,[H+] and [OH] of CH3NH2 .

### 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

Find more solutions based on key concepts
The roles of protein in the body include all but a. blood clot formation. b. tissue repair. c. gas exchange. d....

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

CCl4, CBr4, NO, dinitrogen monoxide, sulfur dioxide, sulfur hexafluoride

Introductory Chemistry: An Active Learning Approach

(a) Find the angular speed of the Earths rotation about its axis. (b) How does this rotation affect the shape o...

Physics for Scientists and Engineers, Technology Update (No access codes included)

What are the two kinds of large storms? How do they differ? How are they similar?

Oceanography: An Invitation To Marine Science, Loose-leaf Versin