A sample of propane gas, C3H8, was collected over water at 25 degree Celsius and 745 torr. The volume of the wet gas is 1.25 L. What will be the volume of the dry propane at standard pressure?

Answer 1

Use PV = nRT and solve for V.
For P, use 745 torr - vapor pressure H2O @ 25C.

Answer 2

where would i get N?

Answer 3

As STP a certian mass of gas occupies a volume of 790cm3 find the tempreture it will occupy when the pressure 726mmHg and volume is 1000cm3