If 91.5 mol of an ideal gas occupies 69.5 L at 31.00°C, what is the pressure of the gas?

1 Answer

You will need to use the Ideal Gas Law to solve this problem:

#PV = nRT#

Explanation:

To find pressure #(P)#, derive from the Ideal Gas Law:

#P = (nRT)/V#

Gather up your known values, and plug them into the equation.

There are a few points to make here, Temperature #(T)# must be converted to Kelvin.

#R# = Ideal Gas Constant. This can have many forms. The one I used below is the one that I am most familiar with. Be aware of this though, and check which value you should be using per your curriculum.

#n = 91.5 mol#
#V = 69.5L#
#T = 31.0°C + (273.15K) = 304.15K#
#R = 8.314J/(mol*K)#

Finally,

#P = ((91.5mol)(8.314J/(mol*K))(304.15K))/(69.5L)#

#P = (x)atm#