What causes hardness
Integrated Science · Grade 9 · about 40 minutes
Soft rain, soluble rock and time. Take away any one and the water stays soft.
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- 8 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- The physical properties of water
- Water from different sources
- The soap test
- Hard and soft water
- What causes hardness
- Temporary and permanent hardness
- Softening by boiling
- Softening with washing soda
- Softening by distillation
- Comparing the softening methods
- Advantages of hard water
- Disadvantages of hard water
- Advantages and disadvantages of soft water
- Choosing the right water for the job