In terms of timetabled activities, totally variable. You might have timetabled activities every day for one term, then have all your lectures on just two days the next term. There's really no way to control that.
In terms of total time expected to be spent on your studies, as above normally you're expected to be spending an amount of time equivalent to full time work on your studies, including timetabled activities, which works out to about 35-40 per week on average. That said often that average gets skewed due to more time being spent around deadlines/in the run up to exams and less time at quieter periods in the term.
It's really usually not practical to work more than 12-15 hours a week in my opinion while studying full time - and realistically 8-10 is probably more than enough along with your uni activities.