相关实验视频
Updated: Jul 11, 2026

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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
在室温离子液体中确定酸度表
Cécile Thomazeau1, Hélène Olivier-Bourbigou, Lionel Magna
1Institut Français du Pétrole, 1 and 4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France.
Journal of the American Chemical Society
|May 2, 2003
概括
这项研究建立了 Brønsted 酸在 [BMIM][NTf2], [BMIM][BF4]和 [BMMIM][BF4]等离子液体中的酸度尺度. 这种尺度有助于预测它们在酸催化反应中的有效性.
科学领域:
- 物理化学 物理化学
- 绿色化学 绿色化学
背景情况:
- 离子液体 (ILs) 是可调节的溶剂,在催化中具有潜在的应用.
- 了解IL中布伦斯特德酸的酸度对于它们的催化应用至关重要.
研究的目的:
- 建立特定离子液体中布伦斯特德酸的定量酸度表.
- 在酸催化反应中,将离子液酸度与它们的催化性能相关联.
主要方法:
- 使用了光谱光度指标方法.
- 确定哈梅特函数来量化酸度.
- 在1--3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([BMIM][NTf2]),1--3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) 和1--2,3-dimethylimidazolium tetrafluoroborate ([BMMIM][BF4]) 中研究了酸性.
主要成果:
- 在研究的离子液体中成功建立了布伦斯特德酸的比较酸度表.
- 确定的哈梅特函数提供了这些ILs中的酸强度的测量.
结论:
- 开发的酸度尺度为选择适合酸催化反应的离子液体系统提供了一个预测工具.
- 这项研究有助于合理设计基于离子液体的催化系统.
相关概念视频
pH
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Acid/Base Strengths and Dissociation Constants
The relative strength of an acid or base is the extent to which it ionizes when dissolved in water. If the ionization reaction is essentially complete, the acid or base is termed strong; if relatively little ionization occurs, the acid or base is weak. There are many more weak acids and bases than strong ones. The most common strong acids and bases are listed below:
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The reaction between a Brønsted-Lowry acid and water is called acid ionization. For example, when hydrogen fluoride dissolves in water and ionizes, protons are transferred from hydrogen fluoride molecules to water molecules, yielding hydronium ions and fluoride ions:
Weak Acid Solutions
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pH
The potential of hydrogen (pH) is a measure of the acidity or basicity of a water-based solution determined by the concentration of hydronium ions (H3O+). In one liter of pure water at neutral pH, there are 1×10−7 moles of hydronium ions. However, the extensive range of hydronium ion concentrations present in water-based solutions makes measuring pH in moles cumbersome. Therefore, a pH scale was developed to convert moles of hydronium ions into the negative logarithm of the hydronium ion...

