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49
Subjective

How do emulsifying agents stabilise the emulsion?

Explanation

Emulsifying agents stabilise the emulsion by forming an interfacial layer between suspended particles and the dispersion medium. e.g., gelatin is added to ice cream to stabilise it.

50
Subjective

Why are some medicines more effective in the colloidal form?

Explanation

Some medicines are more effective in colloidal form because they have large surface area so easily assimilated in the body.

51
Subjective

Why does leather get hardened after tanning?

Explanation

Animal hide is colloidal in nature and has positively charged particles. When it is soaked in tanin (negatively charged), a colloid, it results in mutual coagulation and gets harden. Thus, leather get hardened after tanning.

52
Subjective

How does the precipitation of colloidal smoke take place in Cottrell precipitator?

Explanation

In Cottrell precipitator, smoke particles (charged) are passed through a chamber containing plates with charge opposite to the smoke particles, smoke particles lose their charge on the plates and get precipitated.

53
Subjective

How will you distinguish between dispersed phase and dispersion medium in an emulsion?

Explanation

To distinguish between dispersed phase and dispersion medium we increase the concentration of any one dispersion medium or dispersed phase then notice the change. When dispersion medium is added to an emulsion, it gets diluted to any extent. But on adding dispersed phase it forms a separate layer, if added in excess.