Ch.16 - Aqueous Equilibrium WorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: Consider the acid-base indicator, HIn, featured below: Hln (aq) +   H2O (l) ⇌ In– (aq) + H3O+ (aq)         K a = 1.0 x 10–4 (yellow)                         (red) Which of the following statements regarding this indicator is FALSE? (a) The indicator gradually changes color over a pH range of ~ 3-5. (b) The predominant color of the indicator in its acid range is yellow. (c) At its end point, the indicator will appear orange. (d) When placed in a neutral solution (at 25°C), the indicator will appear red. (e) This indicator is suitable to use in a titration involving a weak acid with a strong base.  

Problem

Consider the acid-base indicator, HIn, featured below:

Hln (aq) +   H2O (l) ⇌ In– (aq) + H3O(aq)         K a = 1.0 x 10–4
(yellow)                         (red)

Which of the following statements regarding this indicator is FALSE?

(a) The indicator gradually changes color over a pH range of ~ 3-5.

(b) The predominant color of the indicator in its acid range is yellow.

(c) At its end point, the indicator will appear orange.

(d) When placed in a neutral solution (at 25°C), the indicator will appear red.

(e) This indicator is suitable to use in a titration involving a weak acid with a strong base.