How many liters of gas can be produced at STP from 25.0 of ?

Zn(s) + 2HCl(aq)->ZnCl2(aq) + H2(g)
I'm using V=nRT/P and can't get this

V = nRT/P won't get it. This is a stoichiometry problem.

You want to try that or do you need help with it?