I read that CT is the temperature above which a liquid cannot exist, i.e. only exists as supercritical fluid. I also learned that critical pressure is the minimum pressure that can be applied at the CT to liquefy it.
All cool, right?
Well, see these proliferated and confusing statements online:
"The critical temperature of a substance is the temperature at and above which vapor of the substance cannot be liquefied, no matter how much pressure is applied."
"The critical pressure of a substance is the pressure required to liquefy a gas at its critical temperature. Some examples are shown below."
"Make sure that you understand the critical temperature correctly; liquefaction can occur only below the critical temperature if sufficient pressure has been applied to the gas."
How is this possible? I am getting legitimately confused. On one hand, I read that you can apply critical pressure at CT and still be able to liquefy a gas; on another, I read that, "No, you better have the gas below the CT or else it won't liquefy even if you put the pressure of the entire universe into it". Why so confusing??