Zinc Hydroxide Precipitation

ZnSO4 + 2NaOH → Zn(OH)2↓ + Na2SO4

Visão geral

Zinc sulfate reacts with sodium hydroxide to form a white gelatinous precipitate of zinc hydroxide (Ksp = 3.0 × 10⁻¹⁷). Zn(OH)₂ is amphoteric, dissolving in excess NaOH to form the zincate ion [Zn(OH)₄]²⁻. This amphoteric behavior is a diagnostic test for zinc in qualitative analysis.

Participantes

Papel Substância Coeficiente Estado
Reagente Zinc Sulfate ZnSO₄ 1 (aq)
Reagente Sodium Hydroxide NaOH 2 (aq)
Produto Sodium Sulfate Na₂SO₄ 1 (aq)

Exemplo do cotidiano

Calamine lotion contains zinc compounds that form protective precipitates on skin, soothing itching from insect bites and rashes.

Importância industrial

A precipitação de hidróxido de zinco é utilizada na recuperação de zinco de águas residuais, na produção de loção de calamina e como precursor de óxido de zinco.

Frequently Asked Questions

What is the equation for Zinc Hydroxide Precipitation?
The balanced equation is: ZnSO₄ + 2NaOH → Zn(OH)₂↓ + Na₂SO₄.
What type of reaction is Zinc Hydroxide Precipitation?
Zinc Hydroxide Precipitation is a precipitation reaction.
Is Zinc Hydroxide Precipitation exothermic or endothermic?
Zinc Hydroxide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -38.0 kJ/mol.