125. Solving a chemistry problem

Calculate the repulsion energy U of spherical nanoparticles with radius r in an aqueous electrolyte solution with concentration c at the diffuse layer potential φ. Take a temperature of 25 °C and a relative permittivity of the medium of 78.6. The calculation should be made at distances between the surfaces of particles h: 1, 2, 4, 8, 16, 32 nm. Plot U = f(h).

Task Electrolyte с, mmol/l φ, mV r, nm
50 KBr 1,800 27 25