Krypton has its triple point at 115.775 K and 73.2 kPa. The normal (at 101.325 kPa) melting and boiling temperatures are 115.79 K and 119.93 K. Its critical temperature and pressure are 209.41 K and 5500 kPa. With these values, sketch (axes not necessarily to scale) the phase diagram for krypton. Is solid krypton denser than liquid krypton?

Hydrogen has its triple point at 13.8 K and 7.04 kPa. The normal (at 101.325 kPa) melting and boiling temperatures are 14.05 K and 20.28 K. Its critical temperature and pressure are 32.98 K and 1293 kPa. With these values, sketch (axes not necessarily to scale) the phase diagram for hydrogen. At 101.325 kPa, does hydrogen have a stable liquid state?

Which of the following diagrams depicts the distinction between the phase boundaries of a pure solvent and a solution?

A.

B.

C.

Consider the diagram below showing the vapor pressure curves for two solutions with equivalent concentrations. Solution A contains a nonvolatile solute while Solution B contains a volatile solute with a vapor pressure of around half of the vapor pressure of the pure solvent at a certain temperature.

Approximate the vapor-pressure curve for the pure solvent and determine its normal boiling point.

At standard pressure, iodine (I₂) has a melting point of 113.7°C and a boiling point of 184.3°C. Its liquid phase has a density of 3.96 g/cm³ and its solid phase has a density of 4.93 g/cm³. Its critical temperature and pressure are 546°C and 115 atm while its triple point is at 114°C and 0.12 atm. Starting from a point at 75°C and 5.0 atm the following changes were made:

Step 1: The temperature is increased to 200°C at a constant pressure.
Step 2: The pressure is decreased to 0.500 atm at a constant temperature.
Step 3: The temperature is decreased to 115°C at a constant pressure.
Step 4: The pressure is decreased to 0.050 atm at a constant temperature.

Identify the starting phase and final phases of I₂.

Consider a portion of the phase diagram of a substance that has a liquid crystalline state below. Starting from the pressure and temperature at point A, what is the first phase change when the temperature is increased? How will the order of the molecules change? Provide a reason for the change.

Which label is not correct for the phase diagram of a nonliquid crystalline substance?