Question

Which of the following is an example of hydrophobic sol?

• A. Rubber in benzene
• B. Cellulose acetate in acetone
• C. Metal sulphide
• D. Starch in water

Hint:

Hydrophobic sols are colloidal solutions where the dispersed phase is non-polar, like rubber in benzene.

Answer 1

The Correct Option is A

Step 1: Understanding hydrophobic sol.
A hydrophobic sol is a colloidal solution where the dispersed phase is non-polar and does not interact well with water. Rubber in benzene is an example of a hydrophobic sol, as rubber is non-polar and does not mix well with water.
Step 2: Analyzing the options.
(A) Rubber in benzene: Correct — This is an example of a hydrophobic sol.
(B) Cellulose acetate in acetone: Incorrect, this is a hydrophilic sol.
(C) Metal sulphide: Incorrect, metal sulphides are typically hydrophilic, not hydrophobic.
(D) Starch in water: Incorrect, starch in water forms a hydrophilic sol.
Step 3: Conclusion.
The correct answer is (A) Rubber in benzene.