Question

What is a triple point? What is the difference between the triple point and boiling point?

Answer 1

Triple point

• The term triple point refers to the point at which solid, liquid, and vapor phases coexist in equilibrium at a given temperature and pressure for a given substance.
• It can be also said that the point where liquid becomes stable is called the triple point.
• Pure water has a triple point of $0.01°\mathrm{C}(273.16\mathrm{K},32.01°\mathrm{F})$and pressure of$4.58\mathrm{mm}(611.2\mathrm{Pa})$.

Boiling point

• The boiling point is defined as the point at which liquid starts boiling.
• At this point, matter exists in two states known as gaseous and liquid.
• The boiling point of water is $100°\mathrm{C}$.

Difference between Boiling point and Triple point

• In the case of a triple point, all the states of matter exist while in the case of a boiling point only two states of matter exist.
• It is impossible to drop the boiling point below the triple point.