Question

Tyndall effect is more effectively shown by:

• A. true solution
• B. lyophilic colloid
• C. lyophobic colloid
• D. suspension

Hint:

Remember the key difference for Tyndall effect in colloids: Lyophobic (solvent-hating) means a big difference in properties (like refractive index) leading to strong scattering. Lyophilic (solvent-loving) means a smaller difference, leading to weak scattering.

Answer 1

The Correct Option is C

The Tyndall effect, or Tyndall scattering, is a phenomenon in which light is scattered by particles in a colloid or a fine suspension. This effect is used to differentiate between solutions, colloids, and suspensions based on the visibility of the path of light through the medium.

1. True Solution: In a true solution, the particle size is in the range of 1 nm. These particles are too small to scatter light, and hence, the Tyndall effect is not observed. Therefore, true solutions do not show the Tyndall effect.
2. Lyophilic Colloid: Lyophilic colloids are stable colloidal solutions, where the dispersed particles have an affinity for the solvent. The particles are relatively small and tend to remain in solution without scattering much light. Thus, the Tyndall effect is not very prominent in lyophilic colloids.
3. Lyophobic Colloid: Lyophobic colloids are unstable colloidal solutions where the particles have little affinity for the solvent. The particles are larger than those in lyophilic colloids, making them more effective at scattering light. As such, the Tyndall effect is prominently observed in lyophobic colloids.
4. Suspension: In a suspension, the particles are much larger than in colloidal solutions. While suspensions can scatter light, they are generally opaque, making the Tyndall effect less apparent in practical observations.

Based on the above reasoning, the correct answer is lyophobic colloid, as this type of colloid scatters light effectively, making the Tyndall effect readily observable.