What bounce on wedge for pitch shots?

It depends on alot of things, angle of attack, what are the ground conditions you play mostly, is the wedge use for standard pitch shots or do you like to play a variety of shots with the face open, heel up in the air, shaft leaning forward. Grind is just as important as bounce on a wedge. I use a 47 with a full grind and standard bounce, my 52 is the same but my 58 has a touch more bounce and a c grind. Reason for the c grind is I use the 58 in alot of different places, it allows the wedges leading edge to sit closer to the ground when opening the face etc.
If you are relatively new to golf I wouldn't worry too much about it I'd just get a 56 wedge with standard bounce and learn to play different shots with it. Once you get pretty efficient at playing shots maybe worry about different bounces etc.