Question

To an initially evacuated 50.0L container maintained at 155C were added 3.20g of gaseous xenon and 4.00g of gaseous fluorine. A spark was used to initiate reaction between xenon and fluorine, and gaseous xenon hexafluoride was the sole reaction product. What was the pressure inside the container after the reaction occurred to the maximum extent?

Answer 1

This is a limiting reagent problem. I know that because BOTH reactants are given an amount.
Xe + 3F2 ==> XeF6

Convert 3.2g Xe to moles. moles = grams/molar mass.
Convert 4.0 g F2 to moles using the same procedure.
Using the coefficients in the balanced equation, convert moles of each reactant to moles of the product.
Undoubtedly, the two values for the product will not agree; the correct value in limiting reagent problems is ALWAYS the smaller one and the reagent producing that value is the limiting reagent.

Next, you want to use the same process to determine the amount of the non-limiting reagent that remains as unreacted material.

Add moles from XeF6 to moles of the non-limiting reagent and use PV = nRT to solve for P.
Post your work if you get stuck.