Frequently asked intresting facts - 2
What is triple point or what is its significance or what is the difference between triple point and critical point? There are 15 possible diagrams in Thermodynamics which are made with the different-different combination of 6 Thermodynamic properties which are pressure, temperature, volume, internal energy, enthalpy and entropy. Now all these 15 diagrams are constructed by taking a reference point on which all the three form of water exist, that's solid, liquid and gas. That point is known as triple point. Actually if we observe in detail, triple point is not a point in 14 out of 15 diagrams. It is a line and this line is known as triple line. Let me show you in example of 1 diagram out of those 14, that's temperature vs entropy diagram as shown below Likewise 14 diagrams are there on which triple point is a line. Only one diagram is there in which triple point is a point and that is pressure vs temperature diagram. In this diagram phase change region is also absent. P