Barium Hydroxide and Ammonium Thiocyanate (Endothermic)

Ba(OH)2·8H2O + 2NH4SCN → Ba(SCN)2 + 2NH3 + 10H2O

Aperçu

This highly endothermic acid-base reaction absorbs so much heat that it can freeze water beneath the flask. Mixing barium hydroxide octahydrate with ammonium thiocyanate drops the temperature below -20 C. The ammonium ion acts as a weak acid donating protons to hydroxide.

Participants

Rôle Substance Coefficient État
Produit Ammonia NH₃ 2 (g)
Produit Water H₂O 10 (l)

Exemple du quotidien

This is one of the most dramatic endothermic reaction demonstrations, where a wet board freezes to a beaker as the reaction proceeds.

Importance industrielle

This reaction is primarily used as a teaching demonstration of endothermic processes and entropy-driven reactions, illustrating the thermodynamics concept that ΔG = ΔH - TΔS.

Propriétés

Type
Acid-Base
Réversible
Non
Énergie
Endothermique
ΔH
170,0 kJ/mol

Réactions associées

Hydrochloric Acid and Barium Hydroxide Acetic Acid and Sodium Acetate Buffer System Acetic Acid Dissociation in Water Ammonia and Hydrochloric Acid Ascorbic Acid and Sodium Hydroxide Carbonic Acid and Sodium Hydroxide Aluminum Hydroxide as Amphoteric Acid with NaOH Aluminum Chloride and Chloride Ion (Lewis Acid-Base) Acetic Acid and Sodium Hydroxide Neutralization Formic Acid and Sodium Hydroxide

Frequently Asked Questions

What is the equation for Barium Hydroxide and Ammonium Thiocyanate (Endothermic)?
The balanced equation is: Ba(OH)₂·8H₂O + 2NH₄SCN → Ba(SCN)₂ + 2NH₃ + 10H₂O.
What type of reaction is Barium Hydroxide and Ammonium Thiocyanate (Endothermic)?
Barium Hydroxide and Ammonium Thiocyanate (Endothermic) is a acid-base reaction.
Is Barium Hydroxide and Ammonium Thiocyanate (Endothermic) exothermic or endothermic?
Barium Hydroxide and Ammonium Thiocyanate (Endothermic) is endothermic (absorbs energy). The enthalpy change (ΔH) is 170.0 kJ/mol.