One of the mysteries of the English language finally explained.
The presence in water of mineral salts (chiefly calcium bicarbonate) that are removed by boiling.
- ‘There are two types of hardness, resulting from different compounds - permanent and temporary hardness.’
- ‘Calcium bicarbonate is called temporary hardness because it will precipitate out of solution.’
- ‘The term ‘temporary hardness’ is sometimes used, because the hardness is removed by boiling.’
- ‘The water has a lot of temporary hardness from a high level of bicarbonate.’
- ‘Temporary hardness can be precipitated and removed by boiling the water.’
- ‘Make sure you know how and why temporary hardness is removed.’
- ‘When temporary hardness is eliminated by this method, no salts remain.’
- ‘The temporary hardness is caused by the magnesium and calcium bound in hydrogen carbonate or carbonate.’
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