dissociation constant

简明释义

离解常数

英英释义

例句

1.The dissociation constant is a key parameter in understanding the strength of an acid in solution.

在理解溶液中酸的强度时，解离常数是一个关键参数。

2.Chemists often use the dissociation constant to compare the affinities of different ligands.

化学家们常常使用解离常数来比较不同配体的亲和力。

3.In drug design, the dissociation constant helps predict how well a drug will bind to its target.

在药物设计中，解离常数有助于预测药物与其靶标结合的效果。

4.A low dissociation constant indicates a strong acid that dissociates completely in water.

低的解离常数表明一种强酸，它在水中完全解离。

5.The dissociation constant for this enzyme-substrate complex was measured to be 1.5 mM.

这个酶-底物复合物的解离常数测量为1.5毫摩尔。

作文

The concept of the dissociation constant is fundamental in the field of chemistry, particularly in understanding how substances interact in solution. In simple terms, the dissociation constant is a quantitative measure of the tendency of a compound to separate into its constituent ions or molecules in a solution. This is crucial for predicting the behavior of acids, bases, and salts in various chemical reactions.To delve deeper into this topic, we first need to understand what dissociation means. Dissociation refers to the process where a compound breaks down into smaller components, usually ions. For example, when table salt (NaCl) dissolves in water, it dissociates into sodium ions (Na⁺) and chloride ions (Cl⁻). The dissociation constant provides a numerical value that represents the extent of this process. The dissociation constant, often denoted as Kd, is expressed mathematically in the context of a reversible reaction. For a generic reaction where a compound AB dissociates into its ions A⁺ and B⁻, the expression for the dissociation constant can be written as:Kd = [A⁺][B⁻] / [AB]Here, the square brackets denote the concentrations of the respective species at equilibrium. A larger value of the dissociation constant indicates a greater degree of dissociation, meaning that the reaction favors the formation of ions over the intact compound. Conversely, a smaller value suggests that the compound remains largely undissociated in solution.Understanding the dissociation constant is essential for various applications, including pharmaceuticals, environmental science, and biochemistry. In drug development, for instance, the dissociation constant helps scientists determine how well a drug will bind to its target receptor. A drug with a high affinity for its target will have a low dissociation constant, indicating that it remains bound more tightly than one with a higher value.Moreover, the dissociation constant plays a critical role in buffer solutions, which are vital for maintaining pH levels in biological systems. Buffers work by neutralizing small amounts of acids or bases, and their effectiveness is determined by the dissociation constant of the weak acid or base involved. For example, acetic acid (CH₃COOH) has a specific dissociation constant that helps maintain the pH in various biochemical processes.In environmental chemistry, the dissociation constant is used to assess the behavior of pollutants in water bodies. Understanding how pollutants dissociate helps in predicting their mobility and bioavailability, which are critical factors in environmental assessments and remediation strategies.In conclusion, the dissociation constant is a vital parameter in chemistry that facilitates our understanding of molecular interactions in solutions. Its applications span across numerous scientific disciplines, making it an essential concept for students and professionals alike. By grasping the intricacies of the dissociation constant, one can better appreciate the dynamic nature of chemical reactions and their implications in real-world scenarios.

“解离常数”这一概念在化学领域中至关重要，特别是在理解物质在溶液中如何相互作用方面。简单来说，“解离常数”是定量衡量化合物在溶液中分离成其组成离子或分子的倾向的指标。这对于预测酸、碱和盐在各种化学反应中的行为至关重要。深入探讨这个主题，我们首先需要理解解离的含义。解离是指一个化合物分解成更小的组分，通常是离子。例如，当食盐（NaCl）溶解在水中时，它会解离成钠离子（Na⁺）和氯离子（Cl⁻）。解离常数提供了一个数值，表示这一过程的程度。“解离常数”，通常用Kd表示，在可逆反应的背景下以数学形式表达。对于一个一般反应，其中化合物AB解离为其离子A⁺和B⁻，解离常数的表达式可以写为：Kd = [A⁺][B⁻] / [AB]这里，方括号表示平衡时各自物种的浓度。较大的解离常数值表示更大的解离程度，这意味着反应更倾向于形成离子而不是完整的化合物。相反，较小的值则表明化合物在溶液中大部分保持未解离状态。理解解离常数对于各种应用至关重要，包括制药、环境科学和生物化学等领域。在药物开发中，例如，解离常数帮助科学家确定药物与其靶受体结合的效果。与靶标结合紧密的药物将具有低解离常数，表明其比具有较高值的药物更紧密地保持结合。此外，解离常数在缓冲溶液中也起着关键作用，缓冲溶液对于维持生物系统中的pH水平至关重要。缓冲溶液通过中和少量酸或碱来工作，其有效性由所涉及的弱酸或弱碱的解离常数决定。例如，醋酸（CH₃COOH）具有特定的解离常数，有助于维持各种生化过程中的pH。在环境化学中，解离常数用于评估污染物在水体中的行为。了解污染物如何解离有助于预测它们的流动性和生物可利用性，这些都是环境评估和修复策略中的关键因素。总之，解离常数是化学中的一个重要参数，有助于我们理解溶液中分子相互作用的动态特性。它的应用跨越多个科学学科，使其成为学生和专业人士都必须掌握的基本概念。通过掌握解离常数的复杂性，人们可以更好地欣赏化学反应的动态特性及其在现实世界中的影响。