Q4(b). Diffusion-limited current at an electrode
Calculate the diffusion limiting current for the oxidation of an organic compound at an electrode in a quiescent solution. Assume six electrons are involved in the reaction and the thickness of diffusion layer is taken as 0.05 cm in an unstirred solution. Given: (i) Concentration of organic compound, C = 10⁻² mol L⁻¹; (ii) Diffusion coefficient of organic compound, D = 2 × 10⁻⁵ cm² s⁻¹.
Answer in brief
Limiting current density jL = nFDC/δ = 2.3 × 10⁻³ A cm⁻², that is 2.3 mA for each cm² of electrode.
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Coverslimiting currentFick's first lawNernst diffusion layerconcentration polarisationpolarography
All parts of Question 4
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