A 1.93-mol sample of xenon gas is maintained in a 0.805-L container at 306 K. Calculate the pressure of the gas using both the ideal gas law and the van der Waals equation (van der Waals constants for Xe are a = 4.19 L2atm/mol2 and b = 5.11×10-2 L/mol).

Respuesta :

Answer : The pressure of the gas using both the ideal gas law and the van der Waals equation is, 60.2 atm and 44.6 atm respectively.

Explanation :

First we have to calculate the pressure of gas by using ideal gas equation.

[tex]PV=nRT[/tex]

where,

P = Pressure of [tex]Xe[/tex] gas = ?

V = Volume of [tex]Xe[/tex] gas = 0.805 L

n = number of moles [tex]Xe[/tex] = 1.93 mole

R = Gas constant = [tex]0.0821L.atm/mol.K[/tex]

T = Temperature of [tex]Xe[/tex] gas = 306 K

Now put all the given values in above equation, we get:

[tex]P\times 0.805L=1.93mole\times (0.0821L.atm/mol.K)\times 306K[/tex]

[tex]P=60.2atm[/tex]

Now we have to calculate the pressure of gas by using van der Waals equation.

[tex](P+\frac{an^2}{V^2})(V-nb)=nRT[/tex]

P = Pressure of [tex]Xe[/tex] gas = ?

V = Volume of [tex]Xe[/tex] gas = 0.805 L

n = number of moles [tex]Xe[/tex] = 1.93 mole

R = Gas constant = [tex]0.0821L.atm/mol.K[/tex]

T = Temperature of [tex]Xe[/tex] gas = 306 K

a = pressure constant = [tex]4.19L^2atm/mol^2[/tex]

b = volume constant = [tex]5.11\times 10^{-2}L/mol[/tex]

Now put all the given values in above equation, we get:

[tex](P+\frac{(4.19L^2atm/mol^2)\times (1.93mole)^2}{(0.805L)^2})[0.805L-(1.93mole)\times (5.11\times 10^{-2}L/mol)]=1.93mole\times (0.0821L.atm/mol.K)\times 306K[/tex]

[tex]P=44.6atm[/tex]

Therefore, the pressure of the gas using both the ideal gas law and the van der Waals equation is, 60.2 atm and 44.6 atm respectively.