Ch.16 - Aqueous Equilibrium See 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: If a biochemist wishes to prepare a buffer that will be effective at a pH of 3.0 (at 25°C) for studying peptide degradation, what will be the best choice for the acid component? (a) Oxalic acid (H2C2O4), Ka = 5.9 x 10 -2 (b) Hydrofluoric acid (HF), Ka = 6.6 x 10 -4 (c) Pyridinium ion (HC5H5N+ ), Ka = 5.6 x 10 -6 (d) Hypochlorous acid (HClO), Ka = 3.0 x 10 -8 (e) Hydrocyanic acid (HCN), Ka = 6.17 x 10 -10 

Problem

If a biochemist wishes to prepare a buffer that will be effective at a pH of 3.0 (at 25°C) for studying peptide degradation, what will be the best choice for the acid component?

(a) Oxalic acid (H2C2O4), Ka = 5.9 x 10 -2

(b) Hydrofluoric acid (HF), Ka = 6.6 x 10 -4

(c) Pyridinium ion (HC5H5N+ ), Ka = 5.6 x 10 -6

(d) Hypochlorous acid (HClO), Ka = 3.0 x 10 -8

(e) Hydrocyanic acid (HCN), Ka = 6.17 x 10 -10