what is the pH of a 0.40 M Solution of NH 4 NO3(aq)? Kb for NH ₂ (aq) = 1.76X10²5

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
Question
### Determining the pH of a Solution

**Problem Statement:**
What is the pH of a 0.40 M solution of NH₄NO₃ (aq)?

**Given Value:**
- \( K_b \) for \( \text{NH}_3 (\text{aq}) = 1.76 \times 10^{-5} \)

**Explanation:**
To find the pH of a solution of ammonium nitrate (\( \text{NH}_4\text{NO}_3 \)), which is a salt of a weak base \( \text{NH}_3 \) and a strong acid \( \text{HNO}_3 \), you need to consider the hydrolysis of \( \text{NH}_4^+ \).

This involves calculating \( K_a \) using the relation:
\[ K_w = K_a \times K_b \]
where \( K_w = 1.0 \times 10^{-14} \) at 25°C.

**Steps:**
1. Calculate \( K_a \) using:
   \[ K_a = \frac{K_w}{K_b} \]

2. Set up the equation for the hydrolysis of \( \text{NH}_4^+ \):
   \[ \text{NH}_4^+ (aq) + \text{H}_2\text{O} (l) \rightleftharpoons \text{NH}_3 (aq) + \text{H}_3\text{O}^+ (aq) \]

3. Use the equilibrium expression:
   \[ K_a = \frac{[\text{NH}_3][\text{H}_3\text{O}^+]}{[\text{NH}_4^+]} \]

4. Calculate the concentration of \( \text{H}_3\text{O}^+ \) and find the pH:
   \[ \text{pH} = -\log([\text{H}_3\text{O}^+]) \]

This procedure helps in understanding the ionization process in a salt solution and determining the pH effectively.
Transcribed Image Text:### Determining the pH of a Solution **Problem Statement:** What is the pH of a 0.40 M solution of NH₄NO₃ (aq)? **Given Value:** - \( K_b \) for \( \text{NH}_3 (\text{aq}) = 1.76 \times 10^{-5} \) **Explanation:** To find the pH of a solution of ammonium nitrate (\( \text{NH}_4\text{NO}_3 \)), which is a salt of a weak base \( \text{NH}_3 \) and a strong acid \( \text{HNO}_3 \), you need to consider the hydrolysis of \( \text{NH}_4^+ \). This involves calculating \( K_a \) using the relation: \[ K_w = K_a \times K_b \] where \( K_w = 1.0 \times 10^{-14} \) at 25°C. **Steps:** 1. Calculate \( K_a \) using: \[ K_a = \frac{K_w}{K_b} \] 2. Set up the equation for the hydrolysis of \( \text{NH}_4^+ \): \[ \text{NH}_4^+ (aq) + \text{H}_2\text{O} (l) \rightleftharpoons \text{NH}_3 (aq) + \text{H}_3\text{O}^+ (aq) \] 3. Use the equilibrium expression: \[ K_a = \frac{[\text{NH}_3][\text{H}_3\text{O}^+]}{[\text{NH}_4^+]} \] 4. Calculate the concentration of \( \text{H}_3\text{O}^+ \) and find the pH: \[ \text{pH} = -\log([\text{H}_3\text{O}^+]) \] This procedure helps in understanding the ionization process in a salt solution and determining the pH effectively.
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Iodine Titrations
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY