Why does bleeding stop by rubbing moist alum?

Which of the following statements is not correct for lyophilic sols?

In a colloidal solution,both the dispersed phase and dispersion medium are in liquid phase. What is the type of colloid?

Sodium stearate forms in water:

For the coagulation of a negatively charged clay sol in water,the minimum amount of which of the following is required?

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.