The carbon dioxide exhaled by astronauts must be removed from the air. One way to do this is through the use of CO₂ “scrubbers” based on metal hydroxides. CO₂ reacts with the hydroxide to form the corresponding metal carbonate and water. Because these scrubbers need to be sent into space, weight is a significant concern in their design. If the goal is to minimize the mass of metal hydroxide needed to remove a given amount of CO₂ from the air, which would you recommend using: sodium hydroxide, magnesium hydroxide, or aluminum hydroxide? Explain your answer using arguments based on stoichiometry.