Aluminum Hydroxide Precipitation

AlCl3 + 3NaOH → Al(OH)3↓ + 3NaCl

概述

Aluminum chloride reacts with sodium hydroxide to form a white gelatinous precipitate of aluminum hydroxide (Ksp = 3 × 10⁻³⁴). Al(OH)₃ is amphoteric: it dissolves in excess NaOH to form aluminate [Al(OH)₄]⁻. The gelatinous precipitate is an excellent flocculating agent.

参与者

角色 物质 系数 状态
产物 Aluminum Hydroxide Al(OH)₃ 1 (s)
产物 Sodium Chloride NaCl 3 (aq)

日常示例

Water treatment plants use aluminum salts to form Al(OH)₃ flocs that trap suspended particles, clarifying drinking water.

工业重要性

Al(OH)₃絮凝法是全球应用最广的水净化方法。氢氧化铝也用作阻燃剂和抗酸剂。

属性

类型
Precipitation
可逆
否
能量
放热
ΔH
-115.0 kJ/mol

相关反应

Barium Carbonate Precipitation Barium Sulfate Precipitation Cadmium Sulfide Precipitation (Yellow) Calcium Fluoride Precipitation (Fluorite) Calcium Phosphate Precipitation (Bone Mineral) Chromium(III) Hydroxide Precipitation Lead Carbonate Precipitation Lead Chloride Precipitation Calcium Carbonate Precipitation Iron(III) Hydroxide Precipitation

Frequently Asked Questions

What is the equation for Aluminum Hydroxide Precipitation?
The balanced equation is: AlCl₃ + 3NaOH → Al(OH)₃↓ + 3NaCl.
What type of reaction is Aluminum Hydroxide Precipitation?
Aluminum Hydroxide Precipitation is a precipitation reaction.
Is Aluminum Hydroxide Precipitation exothermic or endothermic?
Aluminum Hydroxide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -115.0 kJ/mol.