Soap is the sodium salt of a long chain fatty acid, Sodium salt stearic acis is soluble in water, whereas calcium and magnesium salts are insoluble, so when soap is added to soft water, it dissolves and forms lather readily. Temporary hardness in water can be easily removed by boiling. Permanent hardness can be removed by the addition of washing soda, Calgon process, ion exchange process. Calgon contains

Soap is the sodium salt of a long chain fatty acid, Sodium salt steari

1.	Soap is the sodium salt of a long chain fatty acid, Sodium salt stearic acis is soluble in water, whereas calcium and magnesium salts are insoluble, so when soap is added to soft water, it dissolves and forms lather readily. Temporary hardness in water can be easily removed by boiling. Permanent hardness can be removed by the addition of washing soda, Calgon process, ion exchange process. Calgon contains
Answer» 10 PPM 5 ppm 15 ppm 6 ppm Solution :Hardness of `MgSO_4 = (6G)/(10^3g) = 6`ppm 6gin `10^6g` of watr hardness in terms of `CaCO_3 = 6 XX 100/120 = 5`ppm