Explain the cleaning action of soap . Why do soaps not work in hard water ?

Explanation

Soap is sodium or potassium slat of a higher fatty acid and may be represented as `RCOO^(-) Na^(+)` e.g., sodium stearate `CH_(3)(CH_(2))_(16) COO^(-)Na^(+)` . When dissolved in water , it dissociates into `RCOO^(-)` and `Na^(+)` ions. The `RCOO^(-)` ions , Hard water contains calcium and magnesium salts .
In hard water , soaps get precipitated as calcium and magnesium soap which being insoluble stick to the clothes as gummy mass . The cleaning action of soap is due to the fact that soap molecules form micelle around the oil droplets in such a way that hydrophobic part .