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Weak Base Solutions

Weak Base Solutions

Some compounds produce hydroxide ions when dissolved by chemically reacting with water molecules. In all cases, these compounds react only partially and so are classified as weak bases. These types of compounds are also abundant in nature and important commodities in various technologies. For example, global production of the weak base ammonia is typically well over 100 metric tons annually, being widely used as an agricultural fertilizer, a raw material for chemical synthesis of other...

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Basicity of Aliphatic Amines

Basicity of Aliphatic Amines

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This lesson delves into a critical aspect of the relative strengths of acids and bases. The strength of an acid is evaluated by the acid dissociation into its conjugate base and a hydronium ion in water. The complete dissociation of a strong acid is confirmed with a very high concentration of hydronium ions. As a result, an incomplete dissociation process affirms a weak acid. Therefore, the equilibrium is in the forward direction for strong acids and backward for weak acids in these reactions.

Strong Acid and Base Solutions

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A strong acid is a compound that dissociates completely in an aqueous solution and produces a concentration of hydronium ions equal to the initial concentration of acid. For example, 0.20 M hydrobromic acid will dissociate completely in water and produces 0.20 M of hydronium ions and 0.20 M of bromide ions.

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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

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Structure-based pKa calculations using continuum electrostatics methods.

Carolyn A Fitch¹, Bertrand García-Moreno E

¹Johns Hopkins University, Baltimore, Maryland, USA.

Current Protocols in Bioinformatics

|April 23, 2008

Summary

Understanding protein function requires knowing the pK(a) values of ionizable groups. This study presents structure-based electrostatic calculations to determine these critical values, aiding in protein structure-function analysis.

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Area of Science:

Biochemistry
Structural Biology
Computational Chemistry

Background:

Electrostatic free energy calculations correlate protein structure with function.
Ionizable groups are crucial for protein function, necessitating knowledge of their pK(a) values.
Understanding the molecular determinants of pK(a) is essential for predicting protein behavior.

Purpose of the Study:

To describe protocols for calculating pK(a) values using continuum electrostatics methods.
To provide insights into the molecular determinants of pK(a) values in proteins.
To offer methods for maximizing agreement between measured and calculated pK(a) values.

Main Methods:

Utilizing continuum electrostatics based on the numerical solution of the linearized Poisson-Boltzmann equation.
Employing the finite difference method for electrostatic energy and pK(a) calculations.
Describing two protocols with empirical modifications for enhanced accuracy.

Main Results:

The study details protocols for pK(a) calculations in proteins.
It critically discusses parameters, approximations, and limitations of the employed methods.
Empirically modified protocols aim to improve agreement between calculated and experimental pK(a) values.

Conclusions:

Structure-based pK(a) calculations are vital for understanding protein function.
The described methods, when applied judiciously, offer novel insights into protein properties.
These computational approaches contribute to the study of surface ionizable groups in proteins.