Spherical particles, charge flocculated

Problem 11.6 Kinetics of coagulation of a hydrosol Negatively charged spherical particles with radius R flocculate at 25 °C in an aqueous Na2S04 solution, with a concentration equal to 0.93 x 10 mol L The viscosity of the solution is 8.9 x 10 kg m s The following results were obtained by particle counting during the flocculation of this colloidal system as a function of time ... 

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