Posted by **yellowone** on Monday, April 23, 2007 at 10:48pm.

how many grams of zinc are required to react with excess acid to make one liter of hydrogen at STP?

i have no clue how to go about this i need help

Write the balanced equation.

Zn + 2HCl ==> ZnCl2 + H2

2. Use PV = nRT to convert 1 L H2 gas to mols OR take the shortcut knowing that 1 mol of a gas occupies 22.4 L at STP.

3. Use the equation to convert mols H2 to mols Zn.

4. Then convert mols Zn to grams Zn.

g Zn = mols Zn x atomic mass Zn.