Aluminum Hydroxide Precipitation

AlCl₃ + 3NaOH → Al(OH)₃↓ + 3NaCl

Visão geral

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.

Participantes

Papel	Substância	Coeficiente	Estado
Produto	Aluminum Hydroxide Al(OH)₃	1	(s)
Produto	Sodium Chloride NaCl	3	(aq)

Exemplo do cotidiano

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

Importância industrial

A coagulação com Al(OH)₃ é o método de purificação de água mais utilizado a nível mundial. O hidróxido de alumínio é também utilizado como retardador de chama e antiácido.

Propriedades

Tipo: Precipitation
Reversível: Não
Energia: Exotérmico
ΔH: -115,0 kJ/mol

Reações relacionadas

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.