posted by J.Gomez .
What is the volume of 0.255 moles of gas held at 1.75atm and 10°C?
0.255 moles * 22.4 liters/mole * (1/1.75)*(283/273) = 3.38 liters
You could also use V= nRT/p
I find it easier to remember that 1 mole occupies 22.4 liters at STP (1 atm and 273 K) , and then use scale factors for other temperatures and pressures, as I have done above.