posted by student .
Equation- Mg + 2HCl -> MgCl2 + H2
What volume of hydrogen at STP is produced from the reaction of 50.0 g of Mg and the equivalent of 75g of HCl?
To get the volume of hydrogen, you need to know how many MOLES of hydrogen are produced. To know this, you need to know how many moles of reactants there are. Do you know how to do that?
OK. So, calculate how many moles of each reactant is present...and then, by youre balanced equation, you know that one mole of Mg forms one mole of H2...it's 1 to 1.
Woops. Yikes! I left something out. Don't forget that twice as many moles of HCl than Mg is required....so, when you do the calculation you see that there are 2.05 moles of HCl and 2.05 moles of Mg present. The Mg all gets used up with half left over...so it's 1.025 moles of Mg + 2.05 moles of HCL goes to 1.025 moles of MGCl2 + 1.025 moles of H2. Sorry if I mislead you by leaving this out!!