Boyle's temperature of a van der Waal's gas is 810 K then at- 30° C, select the correct observation.

Boyle's temperature of a van der Waal's gas is 810 K then at- 30° C,  the correct observation for .$T_C=\frac{8}{27};T_B=240\mathrm{K}\text{ or }-{33}^{\circ }\mathrm{C}$ is Gas can't be liquified at any pressure At $T>T_C$, gas can't be liquefied at any pressure.