The correct answer is D. Peptization is a process of dispersing precipitates into colloidal solution.
Peptization is a process in which a precipitate is dispersed into a colloidal solution. This can be done by adding a small amount of an electrolyte, such as sodium chloride, to the solution. The electrolyte will break down the precipitate into smaller particles, which will then be suspended in the solution.
Peptization is often used to prepare colloidal solutions of metals, such as gold and silver. It can also be used to prepare colloidal solutions of other materials, such as proteins and dyes.
A. Precipitation of colloidal particles is the opposite of peptization. It is the process of forming a precipitate from a colloidal solution. This can be done by adding a large amount of an electrolyte to the solution. The electrolyte will cause the colloidal particles to come together and form a precipitate.
B. Purification of colloids is the process of removing impurities from a colloidal solution. This can be done by a variety of methods, such as filtration, dialysis, and ultracentrifugation.
C. Protection of colloidal solution is the process of preventing a colloidal solution from breaking down. This can be done by adding a protective colloid, such as gelatin or gum arabic, to the solution. The protective colloid will surround the colloidal particles and prevent them from coming together and forming a precipitate.