PH value of distilled water
Distilled water is also known as “Aqua pH5”. The pH value of a liquid indicates how acidic or basic the substance present is. The scale ranges from 0 to 14, where 7 describes a neutral solution.
Smaller numbers indicate that the liquid contains more acid than bases. The closer the number is to zero, the more acidic the solution is. PH values above 7 thus describe basic solutions.
Water in general has a neutral pH value which is between 6 and 8.5. Distilled water also originally has a neutral value of about 7, but as soon as the vessel containing the water is opened, it comes into contact with carbon dioxide from the ambient air and partially reacts to form carbonic acid. This also changes the pH and it drops to about 5.
Conductivity of distilled water
Conductivity is the ability of any chemical substance to transfer energy or particles. Substances with particularly good conductivity for electrical charge or heat are metals. Metals are also known as “superconductors”.
Silver has the highest conductivity of all metals. The unit for conductivity is Siemens per meter, abbreviated S/m. Silver has a conductivity of 63×10^6 S/m.
Water in its pure form is not a good electrical conductor. The conductivity in water is only caused by the dissolved salts, the ions. They can conduct the electric charges away through the liquid.
Water itself has no conductivity. However, completely pure water exists only in theory, because even after several distillations there will still be dissolved particles in the water. Also pure water has the property to produce two ions from two water molecules by the so-called “autoprotolysis”.
Thus even the purest water has a conductivity of 5×10^-6 S/m. Drinking water on the other hand has a conductivity of about 0.01 S/m. This means that distilled water has an enormously lower conductivity than conventional drinking water, but cannot completely cancel it out.