12. Solving a chemistry problem

12. Calculate the EMF of the circuit at 298 K:
(-) (Pt) H2|HClaq|Cl2 (Pt) ( )
if a) the concentration of HCl is 1.0 M and the partial pressure of gases is 1.013 * 105 Pa; b) HCl concentration - 0.1 M and partial gas pressures of 1.013 * 104 Pa. The average activity coefficient of HCl in 1.00 M solution is 0.809 and in 0.1 M HCl is 0.796. The standard electrode potential ½ Cl2-/Cl- is 1.358 V.