Please help with this chem question? got half solved test tommorrow

5)How much hydrochloric acid must be added to an
excess of zinc arsenide in order to obtain 10.0 L of arsine
(AsH3)?

the equation is 6HCl +Zn3As2 -------> 2AsH3 + 3ZnCl2
thats all i could get I keep getting the wrong answer because the answer is suppoused to be 48.881g of HCl

thanks

I assume that you are under STP conditions (1 atm P, 0 C) so I can relate L of AsH3 to moles.

1 mole of any gas at STP has a volume of 22.4 L.

10.0 L AsH3 x (1 mole AsH3 / 22.4 L) = 0.446 moles AsH3

The balanced equation tells us that it takes 6 moles of HCl to produce 2 moles of AsH3.

0.446 moles AsH3 x (6 moles HCl / 2 moles AsH3) = 1.34 moles HCl

HCl has a molar mass = H (1.01) + Cl (35.45) = 36.5 g/mole.

1.34 moles HCl x (36.5 g HCl / 1 mole HCl) = 48.9 g HCl