A container under #2558*"psi"# pressure contains carbon dioxide and whose partial pressure is #54.6*"bar"# and #NO_2#? What is #P_(NO_2)# in atmospheres?

Question

A container under #2558*"psi"# pressure contains carbon dioxide and whose partial pressure is #54.6*"bar"# and #NO_2#?  What is #P_(NO_2)# in atmospheres?

Cameron Andrews · Accepted Answer

The sum of the partial pressures is equal to the total pressure.

In a gaseous mixture, the total pressure is equal to the sum of the individual partial pressures, or the sum of the pressures of the components if they were the only ones occupying the container, according to "Dalton's Law of Partial Pressures". This is a veritable whopper of pressure terms that could only have originated in the United States of America. In any case, the overall pressure is... #P_"Total"=2558*"psi"=(2558*"psi")/(14.7*"psi"*atm^-1)=174*atm=174*"bar................................"# which is a prodigiously high pressure. (Note that #1*"bar"# is as near as dammit equal to #1*atm#). Now #P_"Total"=P_(NO_2)+P_(CO_2)# And so... #P_(NO_2)=P_"Total"-P_(CO_2)=(174-54.6)*atm=119.4*atm#. Given the extremely high pressures involved, the vessel holding these gases would need to be very strong.

Kai Bowman · Answer

undefined $ P_{\text{NO}_2} $ is 56.6 atm.