If You Drop Pennies Inside A Container Of Vinnegar Will It Create Hydrogen Gas?

im just wondering what would happen for an experiment. im pretty sure that when you mix copper (pennies) and Vinnegar (acid) that itcreates hydrogen gas, which is flammable. what i was wondering is
1. is that true
2. would it rise so could you capture the gas with something like a baloon
3. would it be explosive if lighted?
please answer