- #1
terp.asessed
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Homework Statement
Use the data:
P/bar
a: 0.1000
b: 0.5000
c: 1.000
d: 1.01325
e: 2.000
vs.
density/(g/L)
a: 0.1771
b: 0.8909
c: 1.796
d: 1.820
e: 3.652...for an unknown gas at 300K to determine the molecular mass of the gas...
Homework Equations
PV = nRT (b/c of very low pressure)
The Attempt at a Solution
..so, first I plotted the data on a graph, and it seemed like a linear line...considering Pressure is very low, I assumed ideal gas law, as in PV = nRT where n = mass/(molecular mass):
PV = (mass/mm)RT --> mm = (mass/V)(RT/P) = (density)*RT/P...so, I chose one middle data point (c), where:
density = 1.796 g/L
P = 1bar= 0.9869 atm
in addition to given values:
R = 0.082058 L*atm/(mol*K)
T= 300K
and I got mm = 44.80g/mol, which is not the same as 44.10 on the back of the textbook...could someone hint where I made the mistake?