Video Transcript
What solution can be used to remove
carbon dioxide from atmospheric air when preparing nitrogen gas? (A) Sulfuric acid solution, (B)
hydrochloric acid solution, (C) sodium hydroxide solution, (D) copper(II) sulfate
solution, or (E) carbonic acid solution.
In this question, we need to
determine which chemical solution is used to isolate carbon dioxide from atmospheric
air to prepare nitrogen. Nitrogen makes up 78 percent of
Earth’s atmosphere, while oxygen constitutes 21 percent, argon one percent, and
carbon dioxide as well as other gases making up the rest.
It is possible for nitrogen to be
isolated from the air mixture in the laboratory. In order to do so, we need to
remove oxygen gas, carbon dioxide, and water. The laboratory process consists of
a series of steps involving water, sodium hydroxide, concentrated sulfuric acid, and
heated copper.
In the first step, sodium hydroxide
is used to react with carbon dioxide, removing it from the mixture. The following reaction takes
place. Two NaOH aqueous plus CO2 gas
reacts to produce Na2CO3 aqueous plus H2O liquid. As none of the other chemicals
listed are used in the removal of carbon dioxide, we can see that the correct answer
is (C) sodium hydroxide solution.
