Calculate the volume of gas you would expect to be evoleved if X mol of magnesium were reacted with an excess of HCl at standard conditions. Would the answer be X, 22.4X, or 22400X?

Question

Calculate the volume of gas you would expect to be evoleved if X mol of magnesium were reacted with an excess of HCl at standard conditions.  Would the answer be X, 22.4X, or 22400X?

DrBob222 · Answer

X what? 22.4X what? 22,400X what?
Mg + 2HCl ==> MgCl2 + H2

X mol Mg will produce X mol H2. 1 mol occupies 22.4L at STP; therefore, X mols will occupy 22.4X L at STP. So you could have two of the correct answers above if 22.4X is L and 22,400X is mL.