Observation

In (a), some of the candidates defined kinetic theory and diffusion without touching on the specific terms. Many candidates acknowledged either the random motion or the collision between molecules of gases and the walls of their container but failed to state both occurrences to get the full mark.
          In (b), many candidates were able to provide a satisfactory response to the question about the phenomena of light and were able to demonstrate this knowledge.

              EXPECTED RESPONSES:

  (a)        Diffusion of fluid molecules using kinetic theory:
The process where fluid molecules move randomly and collide (1) with neighbouring molecules due to the possession of kinetic energy. (1)

(b)        List of the phenomenon
(i)         Wave;

• Refraction
• Reflection
• Diffraction
• Interference
• Polarization

           (ii)        Particle;

• Photoelectric effect
• Compton effect/scattering
• Thermionic effect
• Black body radiation