Identify triple point.
A) the temperature, pressure, and density for a gas
B) the temperature at which the boiling point equals the melting point
C) the temperature and pressure where liquid, solid, and gas are equally stable and are in equilibrium
D) the temperature that is unique for a substance
E) the temperature at which the solid and liquid coexist

Question

Quizplus · Accepted Answer

The triple point is the temperature and pressure at which all three phases (liquid, solid, and gas) of a substance are equally stable and in equilibrium. It represents a unique point for a particular substance. Choice A refers to the critical point, not the triple point. Choice B refers to the point where the liquid and solid phases have the same vapor pressure, not the triple point. Choice D is not correct as multiple substances can have the same temperature. Choice E refers to the melting point, not the triple point.

Identify Triple Point