Which one of the following statements is NOT correct?

Statement 4 is incorrect because in a micelle, the hydrophobic hydrocarbon tails (non-ionic ends) are oriented towards the interior to interact with the oil droplet, while the hydrophilic ionic ends face outward to interact with water [5]. Soap molecules are indeed sodium or potassium salts of long-chain carboxylic (fatty) acids [2]. They are amphiphilic, containing both a hydrophobic hydrocarbon tail and a hydrophilic ionic head [4]. Detergents are more effective than soaps in hard water because their charged ends do not form insoluble precipitates (scum) with the calcium and magnesium ions present in hard water, allowing them to remain soluble and active [3]. In contrast, soap reacts with these ions to form insoluble salts, reducing its cleansing efficiency [3]. Therefore, the description of the micelle's orientation in statement 4 is the only false claim.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > Activity 4.10 > p. 75
2. [5] https://www.sciencedirect.com/topics/materials-science/soaps-detergent
3. [2] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > CH COOH CH CH OH CH C C CH CH H O 3 3 2 3 2 3 2 Acid O (E - + - - - - - + thanoic acid) (Ethanol) (Ester) O > p. 73
4. [3] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > Activity 4.12 > p. 76