相关实验视频
Updated: Jun 21, 2026

11:16
Hydrophobic Salt-modified Nafion for Enzyme Immobilization and Stabilization
Published on: July 11, 2012
盐酸的冰催化离子化是盐酸的冰催化
1Contribution from the School of Engineering, University College of Borås, SE-501 90, Borås, Sweden.
Journal of the American Chemical Society
|July 27, 2001
概括
盐酸 (HCl) 很容易在平流层冰面上电离,这是一种对臭氧层消耗至关重要的快速过程. 这种表面电离机制解释了观察到的实验结果,并影响了平流层化学.
科学领域:
- 大气化学 大气化学
- 物理化学 物理化学
- 环境科学 环境科学
背景情况:
- 平流层臭氧的消耗是一个重要的环境问题.
- 冰颗粒在平流层化学中的作用,特别是臭氧层的损耗,正在被调查中.
- 在冰上对盐酸 (HCl) 的电离是提出的一个关键步骤.
研究的目的:
- 为了研究平流层冰颗粒上HCl电离的机制.
- 为了确定HCl电离在冰面上的能量可行性.
- 评估这种电离机制对平流层臭氧消耗的影响.
主要方法:
- Ab initio计算使用模型HCl-水集群进行.
- 计算机建模被用来研究电离化过程.
- 理论计算评估了冰面上HCl电离的能量障碍.
主要成果:
- 在冰面上,HCl的电离是一种无障碍的过程.
- 拟议的机制是快速的,并产生暴露的化物阳离子.
- 结果与在低温下在冰上对HCl电离的实验观测一致.
结论:
- 在平流层冰上HCl的表面电离是一种简单快速的过程.
- 这种机制可能对平流层臭氧消耗有很大影响.
- 这些发现补充了现有的理论,并与实验数据保持一致.
相关概念视频
Aqueous Solutions and Heats of Hydration
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
Ions as Acids and Bases
Salts with Acidic Ions
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Common Ion Effect
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
Acid Halides to Carboxylic Acids: Hydrolysis
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
Acid Halides to Esters: Alcoholysis
Alcoholysis is a nucleophilic acyl substitution reaction in which an alcohol functions as a nucleophile. Acid halides react with alcohol to produce esters. The mechanism proceeds in three steps:
Ionic Strength: Effects on Chemical Equilibria
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary cation—the calcium...
In this solution, the primary cation—the calcium...

