The indicator ethyl orange is an acid with a Ka of 4.6 ✕ 10−5. In a 1.9 ✕ 10−4 M solution, it is red in acid and yellow in base. Calculate the pH range over which it goes from 14% ionized (red) to 86% ionized (yellow). (a) pH at 14% ionized (b) pH at 86% ionized

The indicator ethyl orange is an acid with a Ka of 4.6 ✕ 10−5. In a 1.9 ✕ 10−4 M solution, it is red in acid and yellow in base. Calculate the pH range over which it goes from 14% ionized (red) to 86% ionized (yellow). (a) pH at 14% ionized (b) pH at 86% ionized

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter24: Introduction To Spectrochemical Methods

Section: Chapter Questions

Problem 24.1QAP

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Concept explainers

Acid Base Titration

An acid-base titration is the method of quantitative analysis for determining the concentration of an acid and base by exactly neutralizing it with a standard solution of base or acid having known concentration.

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The indicator ethyl orange is an acid with a K_a of 4.6 ✕ 10⁻⁵. In a 1.9 ✕ 10⁻⁴ M solution, it is red in acid and yellow in base. Calculate the pH range over which it goes from 14% ionized (red) to 86% ionized (yellow).

(a)

pH at 14% ionized

(b)

pH at 86% ionized

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