To prepare a sample of hydrogen gas, a student reacts 14.78 grams of zinc with acid:
Zn(s) + 2H (+) = Zn (2+) + H2 (g)
The hydrogen is collected over water at 22 degrees C and the total pressure of gas collected is 768.mm Hg. What is the partial pressure of H2? What volume of wet hydrogen gas is collected?