Which of the following is an emulsifier?

If the dispersed phase is a liquid and the dispersion medium is a solid,the colloid is known as

Detergents $ \text{reduce} $ the surface tension of water.

When a few drops of dilute $HCl$ are added to a freshly prepared precipitate of ferric hydroxide,a reddish-brown colloidal solution is obtained. This phenomenon is known as .......

The process in which colloids, when subjected to a $DC$ electric field, move towards an electrode is known as:

During electro-osmosis of $Fe(OH)_3$ sol,