Electrophoresis:
The movement of colloidal particles towards oppositely charged electrodes in presence of electric filed is called electrophoresis. The movement of colloidal particles towards cathode is called positive electrophoresis and towards anode is called negative electrophoresis.
The nature of charge present on colloidal particle can be determined with the help of electrophoresis. Example:
Colloidal particles of As2S3 move towards anode in the presence of electric field so these colloidal particles are negatively charged.
Charged colloidal particles loose their charge by reaching oppositely charged electrode on passing electric current.
Now, neutral colloidal particles on aggregation, coagulate to form large particles.
