Which of the following laws or theory cannot be explained by the application of the kinetic theory of gases?

Step 1: Analyze the question We need to find the option that the kinetic theory of gases does not explain. The kinetic theory deals with the behaviour of gas particles: their motion, collisions, pressure, temperature and volume.

Step 2: Recall the concept The kinetic theory of gases says that:

• Gases consist of tiny particles in constant, random motion.
• The particles collide elastically with each other and with the walls of the container, and these collisions produce pressure.
• The average kinetic energy of the particles is proportional to the absolute temperature (K).
• The particles have negligible volume, and there are negligible forces between them.

Step 3: Test each option

• B. Charles' law (V ∝ T at constant P): Explained. Raising the temperature increases the particles' kinetic energy, so they hit the walls harder and more often. The volume must expand to keep the pressure constant.
• C. Boyle's law (P ∝ 1/V at constant T): Explained. A smaller volume means more frequent collisions with the walls, so the pressure is higher.
• D. Gay-Lussac's law (P ∝ T at constant V): Explained. Higher temperature means faster particles and more forceful collisions, so the pressure rises.
• A. Dalton's atomic theory: This theory says matter is made of indivisible atoms, that atoms of an element are identical, and that atoms combine in simple whole-number ratios. It concerns the nature and combination of atoms, not the motion, pressure or volume of gases. The kinetic theory does not explain it.

(Dalton's law of partial pressures can be explained by kinetic theory, but Dalton's atomic theory is a different thing.)

Step 4: Answer The correct answer is A. Dalton's atomic theory.

Tip: Boyle, Charles and Gay-Lussac all link pressure, volume and temperature, which are the variables kinetic theory describes. If an option is about atoms combining or the structure of matter instead, it is probably the odd one out.