posted by Anonymous .
Zinc combines with hydrochloric acid to form aqueous zinc chloride and hydrogen gas. If 300.0 mL of a 0.150 M solution of HCl is allowed to react with excess zinc, how many moles of hydrogen gas would be produced? Part two: if this reaction happens at STP what volume of hydrogen gas is produced? (write a balanced equation first)
Write and balanced the equation.
Zn + 2HCl ==> ZnCl2 + H2
How many moles HCl do you have? That's M x L = 0.150 x 0.300 = ??
Use the equation to convert mols HCl to moles H2.
mols H2 = moles HCl x (1 mol H2/2 mols HCl) = moles HCl x (1/2) = ? = moles H2.
If at STP, the volume will be
?mols H2 x 22.4 L/mol = ? L H2 @ STP.