Flashcards
Hard and soft water
Cards in this deck (6)
- 1Name the two types of hard water.Permanent and temporary
- 2What are the differences between the two types of hard water?Permanent hard water contains magnesium sulfate and calcium sulfate ions.
Temporary hard water contains magnesium hydrogen carbonate and calcium hydrogen carbonate ions. - 3Describe the creation of temporary hard water.Carbon dioxide in air an clouds rains onto mountains made of limestone. This is Ca2+ and creates calcium hydrogen carbonate.
- 4How do you soften water?Temporary hard water can be softened by boiling it.
Ca(HCO3)2 is heated to create CaCO3 (s) ,which is limescale, and carbon dioxide. - 5How do you soften hard water?Permanent hard water can be softened by using washing soda or using an ion exchange resin.
Washing powder- Calcium ions + sodium carbonate ----> soluble sodium ions + calcium carbonate. - 6Explain how an ion exchange column works.The column contains beads of ion exchange resins- these are insoluble and negatively charged. the beads are coated with sodium which has a positive 1 charge. Because calcium and magnesium ions have a greater positive charge, they displace sodium on the resin beads. The sodium is soluble so it dissolves in the water.
There will be a point when the column needs to be replaced as the calcium and magnesium will not be attracted to the resin beads anymore.
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- Description
- Short flashcards on how to soften water.
- Created by
- greenchloe1998
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