- Hard water
- Water that lathers easily with soap is said to be soft water. Hard water uses more soap to produce lather because it contains dissolved compounds that react with the soap to form an insoluble solid called scum.
- If the water is in contact with rocks, it may contain calcium and magnesium, which will react with soap so the water is hard.
- When heated temporary hard water produces an insoluble solid called scale. It can be deposited in boilers and in kettles e.c.t. It reduces teh efficiency of the heating equipment and can block pipes.
- Calcium compounds are good for health; strong bones and teeth. They can also help reduce heart disease.