Phase Change Diagram

Subject Study

AP Objective

The student is able to explain the properties (phase, vapor pressure, viscosity, etc.) of small and large molecular compounds in terms of the strengths and types of intermolecular forces.

Multiple Choice Questions: 1

Multiple Choice Question: 2

At a certain pressure and temperature, the gas you are testing refuses to liquefy. What is a possible cause for this?

  • a. A lower pressure is needed to liquefy the gas
  • b. The gas has gone past the critical pressure
  • c. The temperature and pressure need to be equal
  • d. The gas has gone past the critical temperature

Answers and Explanations to Question 1

A) Wrong, Molecules don't form bonds with increase temperature.

B) Wrong, The temperature doesn't have to be three times the pressure to make a triple point.

C) Correct, A triple point is where all states of matter are in equilibrium.

D) Wrong, The states of matter don't coexist at a triple point.