What is the critical temperature defined as?

The critical temperature is defined as the temperature above which a substance cannot exist as a liquid, regardless of the pressure applied. At this temperature, the kinetic energy of the molecules is so high that they cannot form intermolecular bonds strong enough to enter the liquid phase, even when the pressure is increased. This concept is critical in understanding phase transitions and the behavior of substances in different states.

For example, in terms of a gas, if you were to heat a substance like water above its critical temperature, no amount of pressure would allow it to condense into a liquid; it would remain in a gaseous state. Understanding this concept is essential in fields such as materials science, chemistry, and thermodynamics, as it helps predict how substances will behave under varying conditions.