Rotating Disc Electrodes and Reynolds Number

14 Rotating Disc Electrodes and Reynolds Number Problem 

Calculate the Reynolds number for a rotating disc of 5 mm diameter spinning in water and acetonitrile at i) 5 Hz and ii) 25 Hz. Comment on the implication of the values you calculate. The kinematic viscosities of water and acetonitrile at 25°C are 0.01 cm s and 4.4 x 10 cm s respectively. 

In all cases, Re is well below the threshold for the onset of turbulence. Accordingly, the hydrodynamics of the solution will follow a description assuming laminar flow. 

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