on the phase diagram called the critical point. This reflects the fact that, at extremely high temperatures and pressures, the liquid and gaseous phases become indistinguishable, in what is known as a supercritical fluid. In water, the critical point occurs at around T_c = 647.096 K, p_c = 22.064 MPa and ?_c = 356 kg/m³.

The existence of the liquid-gas critical point reveals a slight ambiguity