What is distilled water?

Distilled water - you should know that

For many chemical, physical and biological experiments you need distilled water, for example as a solvent for other substances. After all, one wants to prevent substances already present in water from influencing the experiment in any (unpredictable) way.

• In the sciences, distilled water is also used under the term "Aqua dest". "Aqua" is the Latin name for "water".
• Normal water from springs always (albeit to a small extent) contains trace elements, ions and often other impurities. These additional substances are added to the water during the so-called. Distillation (see below) withdrawn, so that - depending on the degree of distillation - (almost) only water in the form of H₂O molecules is included.
• However, some of these molecules split into ions even in distilled water (H.
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  ⁺Ions as well as OH^-Ions), so that even absolutely pure water has a certain, albeit low, electrical conductivity.
• By the way, the pH of distilled water is 5.


Distilled water: determine the freezing point - this is how it works

A nice experiment that anyone can do at home is determining the ...

• Incidentally, distilled water is not identical to sterile water, an important requirement for drinking water, for example.
• Distilled water should not be drunk in large quantities.

Distilled water - this is how it is produced

Distilled water can be bought in bottles in drugstores and hardware stores for a wide variety of uses. But how is it actually made?

• The simplest way to produce distilled water is actually by distillation, a term most people know from alcohol distilling.
• Normal spring or tap water is first evaporated at a temperature of more than 100 ° C, the boiling point of the water under normal conditions, and then condensed again. The distillation of alcohol works in a similar way, but at different temperatures.
• The distillate obtained is then largely free of the substances previously contained, in particular salts and other chemical compounds.
• Particularly pure water is obtained by double or multiple distillation.
• However, this procedure for obtaining distilled water is complex and in principle only necessary for scientific experiments. For everyday use it is generally sufficient to use demineralized water instead of distilled water. Foreign ions were removed from normal water by ion exchange.
• By the way: Strictly speaking, the water from condenser dryers is not distilled water, but it can be used for the iron, for example.