Notes are being written
The board questions below are real and complete — they come from the CBSE papers themselves. The written notes for this topic are still being prepared.
Board questions on this topic
2 from the CBSE papers we hold — the exact wording the board used.
2026MCQ·1 mark·Q20
While washing dirty clothes by soap, micelles are formed. Select the correct statement about micelles.
- (a) The hydrophobic tail of the soap molecule is in the interior of the cluster, whereas hydrophilic end is on the surface of the cluster.
- (b) The hydrophobic tail is on the surface of the cluster, whereas hydrophilic end is in the interior of cluster.
- (c) Both hydrophobic tail and hydrophilic end are in the interior of the cluster.
- (d) Both hydrophobic tail and hydrophilic end are on the surface of the cluster.
2023Long answer·5 marks·Q34(b)
(i) With the help of diagram, show the formation of micelles, when soap is applied on oily dirt. (ii) Take two test tubes X and Y with 10 mL of hard water in each. In test tube 'X', add few drops of soap solution and in test tube 'Y' add a few drops of detergent solution. Shake both the test tubes for the same period. (1) In which test tube the formation of foam will be more? Why? (2) In which test tube is a curdy solid formed? Why?