A 1-\rm L flask is filled with 1.35 g of argon at 25 {\rm ^\circ C}. A sample of ethane vapor is added to the same flask until the total pressure is 1.15 atm.What is the partial pressure of argon, P_Ar, in the flask?What is the partial pressure of ethane, P_ethane, in the flask?

2 answers

Assuming 1-\rm L flask means 1L flask and 25{\rm^\circ C} means 25 degrees C, then
Use PV = nRT to find the partial pressure of Argon. You know n = grams/atomic mass, R, T, and V. Solve for P.
Then use Ptotal = Pethane + PAr to solve for Pethane.
I have asked repeatedly what \rm means and what {rm^\circ} means with no response at all. If we don't know the symbols you use, perhaps we are giving the wrong answers.
To Dr. Bob, those are font codes for a chemistry homework website, MasteringChemistry . com The students are copy and pasting the questions directly and not proofreading.

ex 1-/rm L means 1L, when on the site, the L is in a different font. And 25{\rm^\circ C} means 25 (the degree bubble) C