Substance X was simulated at standard pressure (1.0 atm) at three different temperatures
CHEMISTRY · Multi-part · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
Substance X was simulated at standard pressure (1.0 atm) at three different temperatures, producing three separate microscopic snapshots. Each snapshot is verbally described below.
• Sample A: Particles occupy fixed positions in a repeating three–dimensional pattern. Each particle oscillates about a mean position but does not translate.
• Sample B: Particles remain in close contact at all times but continuously exchange neighbors, sliding over and around one another. Short-range order exists, but no long-range positional pattern is observed.
• Sample C: Particles are separated by distances much larger than their own diameters, travelling in straight lines until occasional collisions occur. No persistent contacts are observed.
Answer the following questions about the three samples.
(1) For each sample (A, B, and C), identify the physical phase of Substance X.
(2) For each identification in part (a), cite two specific pieces of evidence from the corresponding microscopic description that support your classification.
(3) Rank the three samples from strongest to weakest intermolecular forces. Justify your ranking using features of particle spacing and motion described above.