Iodine and Sodium Thiosulfate Titration

I₂ + 2Na₂S₂O₃ → Na₂S₄O₆ + 2NaI

Visão geral

Iodine oxidizes thiosulfate to tetrathionate while being reduced to iodide. This is the basis of iodometric titration, one of the most important analytical techniques in chemistry. Starch indicator turns blue-black with iodine and becomes colorless at the endpoint when all I₂ is consumed.

Participantes

Papel	Substância	Coeficiente	Estado
Reagente	Iodine I	1	(aq)

Exemplo do cotidiano

The vitamin C content of fruit juice can be determined by iodometric titration, where ascorbic acid reduces iodine before the starch endpoint.

Importância industrial

A titulação iodométrica é um método analítico padrão utilizado no controlo de qualidade da água, análise de antioxidantes em alimentos e determinação de cloro residual. É um dos métodos volumétricos mais fiáveis e amplamente utilizados em laboratórios de análise.

Propriedades

Tipo: Redox
Reversível: Não
Energia: Exotérmico
ΔH: -140,0 kJ/mol

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Frequently Asked Questions

What is the equation for Iodine and Sodium Thiosulfate Titration?

The balanced equation is: I₂ + 2Na₂S₂O₃ → Na₂S₄O₆ + 2NaI.

What type of reaction is Iodine and Sodium Thiosulfate Titration?

Iodine and Sodium Thiosulfate Titration is a redox reaction.

Is Iodine and Sodium Thiosulfate Titration exothermic or endothermic?

Iodine and Sodium Thiosulfate Titration is exothermic (releases energy). The enthalpy change (ΔH) is -140.0 kJ/mol.