# The mass percent of a three component gas sample is 11.0% #BF_3#, 74.5% #CO# and 14.5% #PF_3#. How do you calculate the partial pressure (torr) of #BF_3# if the total pressure of the sample is 0.480 atm?

##### 1 Answer

#### Answer:

This is a good question, and embraces several gas laws....

#### Explanation:

We assume an

And we work out

And so

And note that the individual mole fractions SUM to UNITY, as required...

Now in a gaseous mixture, pressure clearly is proportional to the number of moles...and the partial pressure of EACH component is proportional to the mole fraction expressed by each component...and the constant of proportionality is the mole fraction...