Zusammenfassung der Ressource
Water
- Hard
Anmerkungen:
- How to soften:
-Remove the calcium and magnesium ions by:
a) Add sodium carbonate
b) Ion exchange columns
- Permanent
- Remains hard when boiled
- Temporary
- Softened when boiled
- Contains hydrogencarbonate ions (HCO3).
These decompose on heating to produce
carbonate ions which react with calcium and
magnesium ions to form precipitates.
- Disadvantages
- More expensive
- Causes limescale which reduces
efficiency of electrical appliances
- Advantages
- Calcium compounds good for bones
- Reduced heart disease
- Soft