Question

When a colloidal solution is viewed from the direction at right angles of the light beam, the path of the beam is illuminated due to scattering of light. In the given figure (A) and (B) are:

• A. A - Tyndall cone, B - Scattered light
• B. A - Scattered light, B - Tyndall cone
• C. A - Tyndall cone, B - Blind spot
• D. A - Tyndall effect, B - Tyndall cone

Answer 1

The correct option is A A - Tyndall cone, B - Scattered light

• Colloidal solutions viewed in the dark may appear reasonably clear or translucent by the transmitted light but they show a mild to strong opalescence when viewed at right angles to the passage of light, i.e., the path of the beam is illuminated by a bluish light. This effect is termed as Tyndall effect.

• The bright cone of the light is called Tyndall cone. The Tyndall effect is due to the fact that colloidal particles scatter light in all directions in space.
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• This scattering of light illuminates the path of the beam in the colloidal dispersion.
  
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• Here, in figure A represents Tyndall cone and B represents scattered light in colloidal solution.