Magnesium reacts with hydrochloric acid in a sealed container, as shown. The initial pressure inside the container is 1.20 atm and its volume is 100 mL. What is the pressure inside the container after 243 mg of magnesium has reacted? (Note: Assume the reaction is isothermal and the gas behaves ideally.)
Mg(s) + 2HCl(aq) â MgCl2(s) + H2(g)
(30 degrees celsius)