Other · Multi-part · GCSE · Chemistry · Using Resources · Potable water
Problem
Explain the following.
- Industry normally requires water which has been softened.
- Hard water is good for the promotion of healthy bones and teeth.
- Hard water causes kettles to fur. This 'fur' can be removed by using a dilute acid.
- Hard water wastes soap.
- Hard water can coat lead pipes and reduce the possibility of lead poisoning.
(i) ∣x∣=5
(ii) ∣x∣=−5
(iii) ∣x∣<5
(iv) ∣x∣<−5
(v) ∣x∣>−5
(vi) ∣x∣>5