1011. Solving a chemistry problem

81. Calculate the zeta potential of iron(III) oxide hydrosol particles with a radius of 8.1 nm, for which an electrophoretic mobility of 1.42*10-9 m2/(V*s) was measured in an aqueous solution with an ionic strength of 3.3 mmol/ l at 25 C. The viscosity of the dispersion medium is 0.8903 mPa*s, the relative dielectric constant is 78.36.