17. Solving a chemistry problem

98. When polarography of a thallium solution against the background of a 0.1 M ammonium sulfate solution using a mercury drop electrode, the following data were obtained: at E \u003d -0.36 V, the wave height on the polarogram h \u003d 5 mm; at E = –0.49 V, h = 140 mm, at E = –0.70 V and its subsequent values h = 165 mm. Calculate, using the polarographic wave equation, the half-wave potential and the number of electrons involved in the process.