Distilled water

Water purified by condensing it from steam

Distilled water is water that has been purified by boiling it into vapor and condensing the vapor back into liquid in a separate container. Any impurities in the original water, such as non-volatile or mineral components, that do not boil below or near the boiling point of water remain in the original container. For example, water escaping as steam from a boiler of heating system or steam engine, leaves behind any dissolved materials, which leads to mineral deposits known as boiler scale.

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