Question

True solution shows Tyndall effect. If true enter 1, else enter 0.

Answer 1

Hint: For the Tyndall effect to occur the size of the particle in the solution, that causes the scattering of the light beam as it collides with it, deflecting it from its straight-line trajectory is of prime importance. It should be close to the wavelength of the light for the interaction to occur.

Complete answer:
Firstly, the Tyndall effect is based on the phenomenon of scattering of light. As the beam of light is made to pass through the solution, its path is made visible, due to the significant interaction between the particles of the solution and the beam of light.
But this is possible only if the size of the particle is comparable to the wavelength of the light, that is, ranging between 40-900 nm which is close to the wavelength of visible light (400-750 nm). Thus, causing more interaction with the particles, that results in more scattering of light.
So, the true solution where the particle size is less than 1 nm, the beam of light on passing through it, is unable to interact. Thus, there is no collision and scattering of the light. It simply transmits through the solution in a straight line.
Whereas, in colloidal solution and fine suspensions which are heterogeneous mixtures, have the size of the particle between 1-1000 nm and above, shows the scattering of light in all directions. Thus, the trajectory of the beam of light deviated from the straight line is visible.
Thus, it is used to differentiate between the true and the colloidal solutions. As the true solutions do not show Tyndall effect.

Note:
The effect can be seen in daily life like the blue colour of the iris and the sunlight passing through the canopy of dense forest. It is also used in nephelometers to determine the size and density of particles.