Arturo O. answered • 03/24/17
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I will explain how to solve this, and you can do the math.
Assume ideal gas behavior.
PV = nRT
P = nRT / V
P = pressure = ?
n = number of moles = mass of gas (given) divided by molecular weight of C3H8 (add atomic weights of 3C and 8H)
R = universal gas constant (look up in your chemistry book)
T = absolute temperature = (22 + 273) K = 295 K
V = volume (given)
Plug in the numbers and get P from
P = nRT / V
Be careful with the units. Can you finish from here?
Arturo O.
This time use
V = nRT / P
If the amount of gas is the same, use the same n as before, and R is a constant. But T and P are different this time. What is the definition of STP? If I recall correctly, STP is 0°C (i.e. 273 K) and 1 atm. Use these values, always using absolute temperature, and convert 1 atm to the more familiar metric units of Pa (N/m2). Again, be careful with the units.
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03/24/17
J.R. S.
tutor
An easier way is to know that at STP 1 mole of ANY ideal gas occupies 22.4 L. So, multiply the mole of propane (0.0522) x 22.4 to get liters. And Arturo is correct that STP is 0ºC = 273ºK and 1 atm.
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03/24/17
Hailey T.
03/24/17