Question

Which phases of a substance can exist when the pressure is less than the pressure of the triple point?

A. Solid and Liquid
B. Solid and Vapor
C. Liquid and Vapor
D. Solid, Liquid and Vapor

Answer 1

If we look at a phase diagram, we can see that at pressures below the triple point, the substance cannot exist in the liquid state regardless of temperature.
The answer is B. Solid and Vapor.