Vitamin C as Reducing Agent

C6H8O6 + I2 → C6H6O6 + 2HI

Visão geral

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.

Participantes

Papel Substância Coeficiente Estado
Reagente Ascorbic Acid C₆H₈O₆ 1 (aq)
Reagente Iodine I 1 (aq)

Exemplo do cotidiano

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

Importância industrial

O doseamento iodimétrico de vitamina C é um método padrão de controlo de qualidade farmacêutica. A ação antioxidante do ácido ascórbico nos alimentos baseia-se nas suas propriedades redutoras.

Propriedades

Tipo
Redox
Reversível
Não
Energia
Exotérmico
ΔH
-58,0 kJ/mol

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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.