Acetic Acid Dissociation in Water

CH3COOH + H2O ⇌ CH3COO− + H3O+

概述

Acetic acid partially dissociates in water with Ka = 1.8 × 10⁻⁵, meaning only about 1.3% of molecules ionize in a 1 M solution. This equilibrium is the archetypal weak acid dissociation used to teach acid ionization constants, ICE tables, and the relationship between Ka and pH.

参与者

角色 物质 系数 状态
反应物 Acetic Acid CH₃COOH 1 (aq)
反应物 Water H₂O 1 (l)

日常示例

Vinegar (5% acetic acid) has a pH around 2.4 because the weak acid only partially ionizes, unlike strong acids that fully dissociate.

工业重要性

理解弱酸平衡对于配制缓冲液、药物制剂以及控制发酵过程中的pH至关重要。

属性

类型
Acid-Base
可逆
是
能量
吸热
ΔH
0.4 kJ/mol

相关反应

Hydrochloric Acid and Barium Hydroxide Acetic Acid and Sodium Acetate Buffer System Ammonia and Hydrochloric Acid Ascorbic Acid and Sodium Hydroxide Barium Hydroxide and Ammonium Thiocyanate (Endothermic) Carbonic Acid and Sodium Hydroxide Aluminum Hydroxide as Amphoteric Acid with NaOH Aluminum Chloride and Chloride Ion (Lewis Acid-Base) Acetic Acid and Sodium Hydroxide Neutralization Formic Acid and Sodium Hydroxide

Frequently Asked Questions

What is the equation for Acetic Acid Dissociation in Water?
The balanced equation is: CH₃COOH + H₂O ⇌ CH₃COO⁻ + H₃O⁺.
What type of reaction is Acetic Acid Dissociation in Water?
Acetic Acid Dissociation in Water is a acid-base reaction. It is reversible under certain conditions.
Is Acetic Acid Dissociation in Water exothermic or endothermic?
Acetic Acid Dissociation in Water is endothermic (absorbs energy). The enthalpy change (ΔH) is 0.4 kJ/mol.