Which of the following is an example of a colloidal solution?

When a sulphur sol is evaporated sulphur is obtained. On mixing with water sulphur sol is not formed. The sol is

Butter is a colloid form in which :

The concentration of electrolyte required to coagulate a given amount of ${\rm{A}}{{\rm{s}}_2}{{\rm{S}}_3}$ sol is minimum in the case of

The separation of colloidal particles (or purification of sol) from particles of molecular dimensions is known as :

An example of dispersion of a liquid in a gas is

Bredig’s arc method cannot be used for the preparation of colloidal sol of

Smoke (a negatively charged colloid) is an example of :

Flocculation value is expressed in terms of :

Which of the following does NOT exhibit the Tyndall effect?

In which of the following reactions colloids are not prepared by the double decomposition method?