Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion. What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g)
(R = 0.08206 L • atm/K • mol)

Question

Quizplus · Accepted Answer

The balanced chemical equation shows that 1 mol of Mg reacts with 2 mol of HCl to produce 1 mol of H2. Therefore, 0.100 mol of Mg will react with 0.200 mol of HCl to produce 0.100 mol of H2. At STP, 1 mol of any gas occupies 22.4 L. Therefore, 0.100 mol of H2 will occupy 2.24 L.

Magnesium Metal (0