2013 · Q78
78. Why does hard water not give lather with soap ?
General KnowledgeChemistry
- AHard water contains Ca and Mg ions which form precipitate with soap
- BHard water contains sulphate and chloride ions which form precipitate
- CpH of hard water is high
- DpH of hard water is less
Explanation
Ca and Mg ions in hard water form precipitate (scum) with soap; the official key marks A.