Zinc Hydroxide as Amphoteric Acid with NaOH

Zn(OH)2 + 2NaOH → Na2[Zn(OH)4]

Aperçu

Zinc hydroxide dissolves in excess sodium hydroxide to form the soluble tetrahydroxozincate complex. This demonstrates zinc hydroxide's acidic character. The initial white precipitate formed by adding NaOH to Zn²⁺ dissolves upon addition of excess base, a key observation in qualitative analysis.

Participants

Rôle Substance Coefficient État
Réactif Sodium Hydroxide NaOH 2 (aq)

Exemple du quotidien

In qualitative analysis labs, students observe the zinc precipitate dissolving in excess NaOH as proof of zinc's amphoteric nature.

Importance industrielle

The zincate solution is used in alkaline zinc electroplating baths, in galvanizing processes, and in the production of zinc oxide.

Propriétés

Type
Acid-Base
Réversible
Oui
Énergie
Exothermique
ΔH
-15,0 kJ/mol

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Frequently Asked Questions

What is the equation for Zinc Hydroxide as Amphoteric Acid with NaOH?
The balanced equation is: Zn(OH)₂ + 2NaOH → Na₂[Zn(OH)₄].
What type of reaction is Zinc Hydroxide as Amphoteric Acid with NaOH?
Zinc Hydroxide as Amphoteric Acid with NaOH is a acid-base reaction. It is reversible under certain conditions.
Is Zinc Hydroxide as Amphoteric Acid with NaOH exothermic or endothermic?
Zinc Hydroxide as Amphoteric Acid with NaOH is exothermic (releases energy). The enthalpy change (ΔH) is -15.0 kJ/mol.