Chlorine gas can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid. How much MnO2 should be reacted with excess HCl to obtain 275 mL of chlorine gas at 5.0 °C and 650 mmHg?
Equation: MnO2(s) + 4HCl(aq) → MnCl2(aq) + 2H2O(l) + Cl2(g)