A researcher is studying the reaction between magnesium (Mg) and hydrochloric acid (HCl), which produces magnesium chloride (MgCl2) and hydrogen gas (H2). The balanced chemical equation for the reaction is:
Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g)
If 0.50 moles of magnesium react with an excess of hydrochloric acid, how many grams of hydrogen gas are produced? (Molar mass of H2 is approximately 2.02 g/mol)