Which postulate of the kinetic molecular theory is not true when considering the formation of clouds in the atmosphere?

• A. Gas particles do not exert attractive or repulsive forces on each other.
• B. The average kinetic energy of gas particles is proportional to the temperature in kelvins.
• C. Gas particles are in constant, random motion.
• D. The volume of individual gas particles is negligible compared to the total volume of the gas.

Answer: (A)

Verified step by step guidance

1. Recall the main postulates of the kinetic molecular theory (KMT) which describe ideal gas behavior, including: (1) gas particles are in constant, random motion, (2) the volume of individual gas particles is negligible compared to the total volume, (3) gas particles do not exert attractive or repulsive forces on each other, and (4) the average kinetic energy of gas particles is proportional to the temperature in kelvins.
2. Understand that the formation of clouds involves condensation, where water vapor particles come together to form liquid droplets. This process implies that there are intermolecular forces acting between the particles.
3. Identify which KMT postulate conflicts with the condensation process: since gas particles must attract each other to form liquid droplets, the postulate stating that gas particles do not exert attractive or repulsive forces is not valid in this context.
4. Recognize that the other postulates (constant random motion, negligible particle volume, and kinetic energy proportional to temperature) still hold true for gases in the atmosphere, even during cloud formation.
5. Conclude that the postulate 'Gas particles do not exert attractive or repulsive forces on each other' is the one that is not true when considering the formation of clouds.