# It was found that in a diving gas mixture for a certain altitude, the total predicted pressure is #"8.38 atm"#. If the partial pressure of oxygen gas must be #"0.21 atm"# underwater, what must the mol fraction be of oxygen gas?

##### 1 Answer

May 18, 2017

This is asking you to use assume

#P_(O_2) = chi_(O_2(g))P_(t ot)# where

#chi_(O_2(g))# is the mol fraction of#"O"_2# in the diving gas mixture and#P_(O_2)# is its partial pressure in the diving gas mixture.

Since we want

#"0.21 atm" = chi_(O_2(g))("8.38 atm")#

#=> color(blue)(chi_(O_2(g)) = 0.025)#

or