The colloid with highest protecting power among the following is
Caesin
Haemoglobin
Gum arabic
Albumen
As we learned in
Properties of Colloidal Solutions -
Coagulation or Precipitation
- wherein
The stability of the lyophobic sols is due to the presence of charge on colloidal particles. If somehow the charge is removed the particles will come nearer to each other and settle down under gravity.
Gold number is the minimum amount of protective colloid in milligrams which presents a color change in gold sol. It is used to describe the protective power of different colloids.
Protective power is inversely proportional to gold number.
Substance Gold number
Caesin 0.01
Haemoglobin 0.03-0.07
Gum Arabic 0.15-0.25
Albumen 0.15-0.25
Clearly, caesin has highest protective power.
Option 1)
Caesin
Correct option
Option 2)
Haemoglobin
Incorrect option
Option 3)
Gum arabic
Incorrect option
Option 4)
Albumen
Incorrect option