Hydrogen Bonding

The temperature at which the vapour, liquid, and solid phases of a substance are in equilibrium is called triple point. For water, the triple point occurs at 273.16 K.

The triple point of water is the single combination of temperature and pressure at which liquid water, gasceres water and ice (solid water) coexist in equilibrium. This triple point occurs at a temperature of approximately and a pressure of 4.58 mm of mercury. On the scale, which use the unit kelvin, the temperature of water at the trpile point was set at 273.1-6 K, abbreviated as 273.16 K. Note: The absolute temperature scale, also called the kelvin scale, employs the SI unit of absolute temperature.