Luminol Chemiluminescence

C8H7N3O2 + H2O2 → 3-aminophthalate + N2 + hν (blue light)

Aperçu

Luminol reacts with hydrogen peroxide in the presence of a catalyst (typically iron from hemoglobin in blood) to produce 3-aminophthalate in an excited electronic state. As the molecule relaxes, it emits blue light (425 nm). The iron in blood catalyzes this reaction, making it a powerful forensic tool.

Participants

Rôle Substance Coefficient État
Réactif Hydrogen Peroxide H₂O₂ 1 (aq)

Exemple du quotidien

Crime scene investigators spray luminol solutions in dark rooms to detect invisible bloodstains that glow blue.

Importance industrielle

Luminol is used in forensic science, analytical chemistry, environmental monitoring, and biological research for detecting trace metals and reactive oxygen species.

Propriétés

Type
Photochemical
Réversible
Non
Énergie
Exothermique
ΔH
-300,0 kJ/mol
Catalyseur
Fe²⁺ (from hemoglobin)

Réactions associées

Photochemical Smog Formation (NO₂ Photolysis) Photochromism of Spiropyran Chlorophyll Fluorescence Photodegradation of Methylene Blue by TiO₂ Photodissociation of Chlorine Gas Silver Bromide Photodecomposition Cis-Trans Isomerization of Retinal Photosynthesis Ozone Formation by UV Light Dye-Sensitized Solar Cell (Grätzel Cell)

Frequently Asked Questions

What is the equation for Luminol Chemiluminescence?
The balanced equation is: C₈H₇N₃O₂ + H₂O₂ → 3-aminophthalate + N₂ + hν (blue light).
What type of reaction is Luminol Chemiluminescence?
Luminol Chemiluminescence is a photochemical reaction.
Is Luminol Chemiluminescence exothermic or endothermic?
Luminol Chemiluminescence is exothermic (releases energy). The enthalpy change (ΔH) is -300.0 kJ/mol.
What conditions are needed for Luminol Chemiluminescence?
This reaction requires a catalyst (Fe²⁺ (from hemoglobin)).