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**Summary::**Find the pressure using the vdw equation in reduced variables

Hi everyone!

I have a doubt when I try to solve this exercise. The result was

**very high pressure**.

Calculate the pressure using the reduced variable vdW equation for a sample of 74.8 grams of ethane in a ##200 cm^3## container and at ##310.5 K##. The ##P_c = 48.2 atm## and ##T_c = 305.4K##

I calculated the correction factors

**a**and

**b**as a function of ##T_c## and ##P_c##

##a=(27R^2T_c^2)/(64P_c)##

##b = (RT_c)/(8P_c)##

**##a=5,489 L^2 atm/mol^2##**

##b=0,0649 L/mol##

##b=0,0649 L/mol##

Then I calculated the

**moles**and then calculated the

**molar volume:**

74.8 gramos = 2,493 mol

##V_m = 0,2L/2,493mol##

74.8 gramos = 2,493 mol

##V_m = 0,2L/2,493mol##

**##V_m = 0,08022 L/mol##**and the van der Waals equation of state:

##(P + \frac{a}{V_m^2})(V_m -b) = RT##

and clearing ##P## and replacing:

##(P + \frac{5.489}{(0,08022)^2})(0.08022 -0.0649) = (0.082)(310.5)##

##P = 808,5 atm##

This is possible?

Is the procedure correct?

Thank you very much for the help