### Determination of Acid Dissociation Constant (Ka) of a Weak Acid**Chemical Reaction:**\[ \text{HA} + \text{KOH} \rightarrow \text{NaA} + \text{H}_2\text{O} \]**Experiment Description:**Nia titrates half of a weak acid solution with KOH until she observes the endpoint. She measures the pH of the half-titrated weak acid solution as 1.23. The task is to determine the \(K_a\) of the acid.**Given Data:**- pH of the half-titrated solution: 1.23**Calculation of Ka:**Since the pH of the half-titrated solution is given, we can use the relationship between pH and the acid dissociation constant \(K_a\).1. **Determine \( [H^+] \):**\[ [H^+] = 10^{-\text{pH}} \]\[ [H^+] = 10^{-1.23} \]2. **Relation between pH and \(K_a\):**At half-titration, \( \text{pH} = \text{p}K_a \)\[ K_a = 10^{-\text{p}K_a} = 10^{-1.23} \]**Interactive Calculation:**Users are prompted to input a coefficient and exponent to express \( K_a \).**Input Fields:**- **Coefficient (green box)**: (Input field)- **Exponent (yellow box)**: (Input field)**Equation:**\[ K_a = [?] \times 10^{[?]} \]**Submission:**After inputting the values, users can click the "Enter" button to check if their answer is correct.This interactive task helps students understand the relationship between pH, pKa, and Ka, and practice calculating these values based on titration data.

Answered: Image /qna-images/answer/e150216f-36e1-48d1-ac61-2fd1cba2e06c.jpg

HA+KOH → NaA + H₂O Nia titrates half of a weak acid solution with KOH until she observes the endpoint. She measures the pH of the half-titrated weak acid solution as 1.23. What is the Ka for the acid? K₂ = [? ] × 10¹² ] a Coefficient (green) Exponent (yellow) Enter

HA+KOH → NaA + H₂O Nia titrates half of a weak acid solution with KOH until she observes the endpoint. She measures the pH of the half-titrated weak acid solution as 1.23. What is the Ka for the acid? K₂ = [? ] × 10¹² ] a Coefficient (green) Exponent (yellow) Enter

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...

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