Aluminum Hydroxide Precipitation

AlCl3 + 3NaOH → Al(OH)3↓ + 3NaCl

概要

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.

参加者

役割 物質 係数 状態
生成物 Aluminum Hydroxide Al(OH)₃ 1 (s)
生成物 Sodium Chloride NaCl 3 (aq)

日常の例

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

産業上の重要性

Al(OH)₃凝集は世界で最も広く使用されている水の浄化法です。水酸化アルミニウムは難燃剤や制酸剤としても使用されています。

特性

タイプ
Precipitation
可逆的
いいえ
エネルギー
発熱性
ΔH
-115.0 kJ/mol

関連する反応

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.