An ideal gas obeying kinetic gas equation can be liquefied if

Explanation

An ideal gas is a theoretical concept that obeys the ideal gas law (PV = nRT) perfectly. However, real gases deviate from this ideal behavior at high pressures and low temperatures. Liquefaction, the process of converting a gas to a liquid, becomes possible under specific conditions for real gases.Here's the key to understanding the liquefaction of an ideal gas: ideal gas behavior breaks down at high pressures and low temperatures. Even though an ideal gas equation exists, it represents a theoretical limit and doesn't apply when strong intermolecular forces become significant due to close proximity of molecules.Therefore, for a real gas to liquefy:High pressure: This overcomes the repulsive forces between molecules and brings them closer together.Low temperature: This reduces the kinetic energy of molecules, further aiding in their attraction and condensation.However, there are limits to these conditions:Critical pressure (Pc): Above this pressure, regardless of temperature, the gas cannot be liquefied. The strong intermolecular forces at this pressure are enough to overcome any thermal motion, keeping the gas in a gaseous state.Critical temperature (Tc): Above this temperature, no matter how high the pressure, the gas cannot be liquefied. The thermal energy of the molecules is too high to be overcome by intermolecular forces, preventing condensation.Therefore, the correct option is c. For an ideal gas (which inherently deviates from ideal behavior at high pressure and low temperature), liquefaction is possible only when the pressure is more than the critical pressure but the temperature is less than the critical temperature.