How Much Hydrogen Gas Is Produced in a Magnesium and Hydrochloric Acid Reaction?

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The reaction between 3.50 g of magnesium and 100 mL of 2.00 M hydrochloric acid produces hydrogen gas and magnesium chloride. The limiting reactant is magnesium, yielding 0.072 moles of hydrogen gas. Using the ideal gas law, the calculated volume of hydrogen gas at standard conditions is 1.61 liters. However, the expected answer is 2.24 liters, indicating a potential error in the calculations. The discussion highlights the importance of careful attention to detail in stoichiometric calculations.
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Homework Statement


3.50 g of magnesium metal is added to 100. mL of 2.00 M aqueous hydrochloric acid. The substances react to completion, producing aqueous magnesium chloride and hydrogen gas (H2). How many liters of pure hydrogen gas, measured at 0.00oC and 1.00 atm are produced in this reaction?

Homework Equations


PV=nRT

The Attempt at a Solution


Rxn Eq: 2Mg + 2HCl --> 2MgCl + H2

3.5 g Mg x (1 mol/24.3g) = .144 mol Mg
2 mol/L HCl x .1L = .2 mol HCl
Mg is limiting reactant

.144 mol Mg x (1 mol H2/2 mol Mg) = .072 mol H2

V=(nRT)/P=[(.072)(.08206)(273)] / 1 = 1.61 L H2

It says the answer is 2.24L?
 
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What is formula of magnesium chloride?

Hint: which periodic table group?

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WOW! I can't believe I missed that. I always miss these on minor mistakes that don't even have to do with the difficult part... Thanks
 
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