27. Solving a chemistry problem

4. For the element Pt(s)|Cu(s)|CuSO4(aq)|Hg2SO4(s)|Hg(l)|Pt(s), write the Nernst equation and calculate the emf at 25 C for a molality of 1 mol/kg CuSO4, knowing the standard EMF of 0.2705 V and taking the activity coefficient of copper sulfate: 1) equal to 1, as if the solution were ideal, 2) equal to 0.0423, as in reality.