This temperature can be seen as the point at which a real gas will approach ideal behavior as pressure approaches zero, and thus for a van der Waals gas is given as the a parameter over the ideal gas constant times the b parameter. For 10 points each:
[10m] Name this temperature at which attractive forces and repulsive forces acting on gas particles balance out—or equivalently, when the second virial coefficient becomes zero.
ANSWER: Boyle temperature
[10e] The second virial coefficient is the second coefficient of the virial expansion of this quantity in powers of the density. This quantity, symbolized Z, describes the deviation of a real gas from ideal gas behavior and equals pV divided by nRT.
ANSWER: compressibility factor
[10h] This contour on a P-V-T diagram marks where the compressibility factor is 1, thus representing an ideal gas. This zeroth-order curve should not be confused with the Amagat curve, where the partial derivative of temperature with respect to pressure at constant volume is zero.
ANSWER: Zeno line [or Zeno curve]
<Neil Gurram, Chemistry>