The sky looks blue due to:

Identify the correct statements from the following:
$(i)$ $A$ closed vessel containing $90 \%$ $CO_2$ and $10 \%$ $O_2$ is an aerosol.
$(ii)$ Milk is an emulsion.
$(iii)$ Smoke is an aerosol.
$(iv)$ Peptisation is a method of purification of colloidal solution.
$(v)$ Ultrafiltration is a method of purification of colloidal solution.

Which of the following ions has greater coagulating power for a negatively charged sol?

Which of the following statements is true for a lyophobic sol?

What is the difference between multimolecular and macromolecular colloids? Give one example of each. How are associated colloids different from these two types of colloids?

Which of the following nanomaterials has all three dimensions less than $100 \ nm$?