Anything done to prepare for the midterm is probably ok, though more specifically Thermochem/Thermodynamics problems as those have been our most recent topics of discussion as we just started Electrochemistry.
My TA said that she would accept midterm outline problems. I don't think it really matters what outline you do for this week as long as it is sort of relevant given the lack of new content this past week.
Vant Hoff equation problems and I imagine some redox reaction problems would be accepted. He only introduced electrochemistry recently so I think any remaining thermochemistry or thermodynamic problems are fine.