The conductivity of demineralized water can vary depending on various factors, including the purity of the water and the temperature. Demineralized water typically has very low conductivity because it has been processed to remove most minerals and ions that contribute to electrical conductivity.
In general, demineralized water has a conductivity in the range of 1-10 microsiemens per centimeter (µS/cm) at 25°C (77°F). However, it's important to note that even demineralized water can contain trace amounts of dissolved gases and impurities, which can slightly increase its conductivity.
It's worth mentioning that if the demineralized water comes into contact with atmospheric carbon dioxide, its conductivity may increase due to the formation of carbonic acid, resulting in the presence of small amounts of ions. Additionally, the presence of dissolved gases and impurities from the environment can contribute to a slight increase in conductivity.
For highly sensitive applications that require extremely low conductivity, such as in certain laboratory experiments or industrial processes, even further purification techniques may be necessary to achieve the desired level of purity and conductivity.