Question

Which of the following will show the “Tyndall effect” ?
1. Salt Solution
2. Sugar Solution
3. Copper sulphate solution
4. Starch Solution

Answer 1

Correct Answer - Option 4 : Starch Solution

The correct answer is Starch Solution.

• The Tyndall effect is the mechanism in which the particles in a colloid scatter the rays of light that are directed at them.
  • All colloidal solutions and some very fine suspensions exhibit this effect.
  • Therefore, it can be used to confirm if a given solution is a colloid.
  • Scattered light intensity depends on the colloidal particle density as well as the incident light frequency.

• Examples of the Tyndall effect
  • Milk makes of a colloid comprising fat and protein globules. The light is spread when a beam of light is directed at a glass of milk. This is a perfect description of the Tyndall effect.
  • The direction of the light becomes evident when a torch is turned on in a foggy atmosphere. The water droplets in the fog are accountable for the scattering of light in this case.
  • Opalescent glass has a bluish appearance when viewed from the side. However, orange-colored light emerges when light is shined through the glass​

• Tyndall Effect Responsible for Blue Eye Colour
  • The primary difference between blue, brown, and black colored irises is the amount of melanin in one of its layers. The layer in a blue iris has relatively lower amounts of melanin in it when compared to a black iris, making it translucent. When light is incident on this translucent layer, it is scattered due to the Tyndall effect.