beacuse it contain dissolve salts of calcium and magnesium salts and other heavy metals and it does not form lather with soap readily..
A scum forms when soap is used in hard water. This occurs because the calcium and magnesium ions in the hard water react with the soap to form insoluble salts, which precipitate out as a scum.
Usually soap holders or soap dispensers are the best for areas with hard water.
Soap cannot be effectively used in hard water areas because the minerals in hard water react with soap to form a scum, which reduces the soap's lathering ability and its cleaning effectiveness. Instead, synthetic detergents, which are formulated to work well in hard water, are recommended for cleaning in such areas.
One effect of soap and detergent in hard water is it will not lather as well as it does in soft water. This can affect the way the soap or detergent cleans in hard water making them less effective.
Hard water.
hard water
Castile soap is best for bathing with hard water.
If you have trouble getting soap out of your hair after washing, the water is most likely hard water. Hard water can cause build up in the hair which can cast a dull appearance. This can be removed with a chelating shampoo.
Water is a universal solvent and there are two types of water i.e hard water and soft water. Soft water is the water that easily lather with soap while hard water does not lather with soap and is also of two type i.e temporary and permanent.
nion
Detergent and soap have similar cleaning properties, though detergents tend to be more effective in hard water as they don't react with minerals like soap does. In soft water, both detergent and soap can effectively clean as there are fewer minerals present.
The water wouldn't form lather(foam) with soap,it would waste soap. It could be cold because most hard water are cold. Solution is boiling,using detergents because it dissolv es than solid or bar soap.