Vitamin C as Reducing Agent

C₆H₈O₆ + I₂ → C₆H₆O₆ + 2HI

Aperçu

Ascorbic acid (vitamin C) reduces iodine to iodide while being oxidized to dehydroascorbic acid. The enediol group on ascorbic acid is the active reducing center, losing two electrons. This reaction is the basis of the standard method for determining vitamin C content in foods.

Participants

Rôle	Substance	Coefficient	État
Réactif	Ascorbic Acid C₆H₈O₆	1	(aq)
Réactif	Iodine I	1	(aq)

Exemple du quotidien

School science experiments often measure vitamin C in different juices by titrating with iodine solution until the starch indicator turns blue-black.

Importance industrielle

Vitamin C iodimetric assay is a standard pharmaceutical quality control method. Ascorbic acid's antioxidant action in food is based on its reducing properties.

Propriétés

Type: Redox
Réversible: Non
Énergie: Exothermique
ΔH: -58,0 kJ/mol

Réactions associées

Iron(II) to Iron(III) Oxidation by Oxygen Bleaching with Sodium Hypochlorite Copper Reduction of Silver Ion Aqua Regia Dissolving Gold Cerium(IV) Reduction by Iron(II) Chlorine Oxidation of Bromide Copper Oxidation by Nitric Acid Hypochlorite Oxidation of Hydrogen Peroxide Hydrogen Peroxide as Oxidizing Agent (Acidic) Displacement of Hydrogen from Acid by Magnesium

Frequently Asked Questions

What is the equation for Vitamin C as Reducing Agent?

The balanced equation is: C₆H₈O₆ + I₂ → C₆H₆O₆ + 2HI.

What type of reaction is Vitamin C as Reducing Agent?

Vitamin C as Reducing Agent is a redox reaction.

Is Vitamin C as Reducing Agent exothermic or endothermic?

Vitamin C as Reducing Agent is exothermic (releases energy). The enthalpy change (ΔH) is -58.0 kJ/mol.