As you know, all animals exhale carbon dioxide in the process of breathing. In a closed
environment such as the space shuttle, a build-up of carbon dioxide can be deadly.
CO2 in high enough concentrations in a closed environment can replace oxygen making
it difficult to breathe enough oxygen to survive. Astronauts in the space shuttle rely on
methods that continuously take carbon dioxide out of the air. A device in the space
shuttle uses lithium hydroxide to remove carbon dioxide. Carbon dioxide will react with
aqueous hydroxide ion to produce hydrogen carbonate ion.

In this lab you build a similar device to remove CO2 from the atmosphere of a petri dish
that uses sodium hydroxide.