Colloidal particles have a very large surface area, so they absorb either a positive charge or a negative charge. That means the colloidal particles are charged. When an electric field is applied to the colloidal mixture, the colloidal particles will move towards the particular electrode and this movement of colloidal particles towards the particular electrode is called electrophoresis. Electrophoresis is classified into two categories. One is called cataphoresis another is called anaphoresis. When the colloidal particles are positively charged then in the presence of electric field the colloidal particles are moved towards the cathode and this process is called cataphoresis. Cataphoresis is observed in the case of \(\tt Fe(OH)_{3}\) solution. Because \(\tt Fe(OH)_{3}\) contain positive charge. When the colloidal particles are negatively charged then in the presence of electric field the colloidal particles are moved towards the anode and this process is called cataphoresis. Blood is a colloidal mixture that contains a negative charge. In this case, anaphoresis takes place.