The Van der Waals equation of state is for real gases that do not behave as ideal gases. This equation is a cubic equation of state, meaning that it gives 3 volume roots. One root will be close to the value of the constant b liquid root) and the other (vapor root) can best be estimated using the ideal gas value of RT/P. A third root is meaningless. P= RT/V-b - a/V^2 where b= RTc/8Pc and a= 27R^2Tc^2/64Pc^2

For methane at 100°C and 15 bar, determine the gas root of Volume using the Van der Waals EOS. You will need to use goalseek function to determine the root. For convenience, the Tc of methane is 190.6 K and Pc = 46.1 bar. Calculate the volume value in liters.