About 12 sets on each muscle, once per week.
Goal: mass building
What is your question?
Would that be sufficient?
I would recommend doing a proven program instead of doing a myriad of lifts you put together yourself. like 5x5 or 5/3/1.
Agreed. Most trainees can do better training the body up to 3x per week.
The thing is, if you want the most from your workout of gym time, you want to be able to train the body as frequently as possible providing it is recovered, and small muscle groups can only take maybe 2 days, larger may 3 or so.
Another thing is, novices and even intermediates are most likely not able to handle the heavy weights advanced guys use. (which is not a dig, it is just a fact of long term regular training.) So that said, the loads a novice will use will be much easier for the body to recover from, which is another reason why, when a trainee first starts lifting, he can gain strength pretty fast and without much mass gain too, since you are learning how to recruit more fibers, teaching the nervous system to respond and improve fiber circulation etc.
You should also think in terms of "compound exercises" and areas of the body ie: chest & shoulders, hips, legs & back, instead of just muscles.
there is a correlation between intensity, volume, and frequency for each person. that all totals up to a value which can be increased as one increases their workout capacity and recovery ability. in others words trick question as the answer changes for each person and over that lifters life time.
as a person above me posted, to make sure you can get great results do a proven program. the best ones have main lifts with set percentages done at set volume and frequency. and they also have accessory work that can be adjusted to ones individual needs.
you can call me "ozzie" for short.