Chemistry

Question Analysis
This question involves using the triple point to predict the phase of a substance on a phase diagram. The main focus is on understanding the significance of the triple point in dividing phase regions.

Key Concept Explanation
The triple point is the only set of conditions where all three phases coexist. Below the triple point pressure, the liquid phase cannot exist—regardless of temperature, the substance will only transition between solid and gas (sublimation/deposition).
Above the triple point temperature and below triple point pressure, the substance will be a gas.

Step-by-Step Solution
1. Recall the behavior of substances below triple point pressure: No liquid phase exists.
2. Analyze the given conditions: Pressure < triple point pressure; Temperature > triple point temperature.
3. Eliminate the liquid phase (...