Hardness of Water

Question 1

What does hard water make and what does this mean?

Answer 1

Scum and scale, which means that you need more water to create a lather when washing hair, and as it is a thermal insulator, kettles may become less efficient.

Question 2

What is hard water caused by?

Answer 2

Ca2+ and Mg2+ ions (calcium and magnesium).

Question 3

What are some benefits of hard water? (2 points)

Answer 3

1) it is better for teeth and bones

2) less chance of getting heart disease due to the minerals

Question 4

How can soft water be made?

Answer 4

By removing the dissolved Ca2+ and Mg2+ in the hard water.

Question 5

What are the two types of hard water and what are they caused by?

Answer 5

1) temporary hardness caused by the hydrogen carbonate ion, and can be removed by boiling, adding sodium carbonate and by running the water through ion exchange columns
2) permanent hardness cause by dissolved calcium sulfate, it can be removed by adding sodium carbonate and running the water through ion exchange columns

Question 6

What do ion exchange columns do?

Answer 6

They have lots of sodium or hydrogen atoms, and exchange them for calcium or magnesium ions in the water.