Water! (Chemistry C3)

How do you soften water?
1. Temporary hard water can be softened by boiling. Permanent hard water is softened by using washing soda or an ion exchange column.
Explain how an ion exchange column works!
1. The column contains sodium ions which are positively charged. The calcium and magnesium ions have a greater charge. Therefore they displace the sodium ions. The sodium is soluable and will dissolve in the water. This means the hard water will now be soft.
Advantages of hard water!
1. 1) CA2+ ions in the water are good for the teeth and bones. 2)Studies show that people who live in a hard water area have a lower risk of developing heart disease.
What causes hardness?
1. Water hardness is caused by the CA2+ and MG2+ ions in the water. This comes from the rocks and mountains that the rain lands on.
what are the two types of hardness?
1. temporary and permanent.
What are the differences between the two?
1. Permanent contains: magnesium sulphate and calcium sulphate ions. temporary contains: magnesium hydrogen carbonate and calcium hydrogen carbonate ions.
Describe the creation of temporary hard water!
1. co2 in the air and clouds rains onto limestone rocks and mountains. Forming CA2+ and creating calcium hydrogen carbonate.

Resource summary

	Created by kane t over 7 years ago