According to the kinetic molecular theory, what distinguishes the movement of molecules in gases compared to those in solids and liquids?

• A. Gas molecules move rapidly and randomly with minimal intermolecular forces.
• B. Gas molecules are closely packed and only move slowly past each other.
• C. Gas molecules rotate but do not translate from place to place.
• D. Gas molecules vibrate in fixed positions within a rigid structure.

Answer: (A)

Verified step by step guidance

1. Recall the key assumptions of the kinetic molecular theory regarding the behavior of molecules in different states of matter: solids, liquids, and gases.
2. Understand that in solids, molecules vibrate in fixed positions within a rigid structure, meaning they have very limited movement.
3. Recognize that in liquids, molecules are closely packed but can move past each other, allowing for flow, though their movement is slower compared to gases.
4. Note that in gases, molecules are far apart and move rapidly and randomly in all directions, with minimal intermolecular forces acting between them.
5. Conclude that the distinguishing feature of gas molecules is their rapid, random motion with minimal intermolecular forces, which contrasts with the restricted movement in solids and the intermediate movement in liquids.