Cod liver oil is

Alum purifies muddy water by

$\Delta$ at the rivers are formed due to:

Which of the following substances is not useful in forming a lyophilic sol?

How is the dispersion medium in Aerosol?

Tyndall effect is observed only when:
$(i)$ the diameter of the dispersed particles is not much smaller than the wavelength of the light used.
$(ii)$ the refractive indices of the dispersed phase and the dispersion medium differ greatly in magnitude.
$(iii)$ the size of the particles is generally between $10^{-11} \ m$ and $10^{-9} \ m$ in diameter.
$(iv)$ the dispersed phase and the dispersion medium can be seen separately in the system.