Lithium hydroxide, LiOH, reacts with carbon dioxide to produce lithium carbonate, Li2CO3. The chemical equation for this reaction is:
2LiOH(s)+CO2(2)-->Li2CO3(s)+H2O(l)
Carbon dioxide is produced every time a person exhales. Some NASA spacecraft rely on this lithium hydroxide reaction to remove exhaled carbon dioxide from the air inside the spacecraft. Air is pumped through a filter containing lithium hydroxide. Inside the filter, carbon dioxide is removed from the air when it reacts with lithium hydroxide to produce lithium carbonate.
a) Describe why the amount of lithium hydroxide present limits the amount of time the astronauts can spend in space?
b) Sodium hydroxide, NaOH, reacts the same as lithium hydroxide and is much cheaper. However, sodium hydroxide is about 40 percent heavier than lithium hydroxide. Why do you think NASA uses LiOH on its space missions?