As a specialist in the field of physical chemistry, I would like to delve into the intricacies of water's conductivity. Water, in its purest form, is a poor conductor of electricity. This is primarily due to the fact that pure water consists of H2O molecules, which do not ionize to produce free-moving ions necessary for electrical conduction. However, the situation changes dramatically when impurities or solutes are introduced into the water.

The conductivity of water is enhanced by the presence of dissolved ions. These ions, which can be from various sources such as dissolved salts, minerals, or other ionic compounds, are capable of moving freely when subjected to an electric field, thereby facilitating the flow of electric current. The more ions present in the water, the higher its conductivity.

Let's consider the process of how water becomes a better conductor. When water acts as a solvent for ionic compounds like sodium chloride (NaCl), it undergoes a process called dissociation. During this process, the ionic compound separates into its constituent ions—sodium ions (Na+) and chloride ions (Cl-). These ions are then free to move within the water, and when an electric field is applied, they move in opposite directions, creating an electric current.

The movement of these ions is what makes water conductive. The conductivity of water is directly proportional to the concentration of these ions. In other words, the higher the concentration of ions, the more conductive the water becomes. However, it's important to note that the type of ions also plays a role. Some ions are more effective at conducting electricity than others due to their charge and mobility.

Another factor that affects water's conductivity is temperature. As the temperature of water increases, the kinetic energy of the water molecules and the dissolved ions also increases. This increased movement results in a higher rate of ion collisions and a greater tendency for ions to move freely, thus enhancing the water's ability to conduct electricity.

Additionally, the purity of water is a critical factor. Pure water, as mentioned earlier, has a very low level of dissolved ions and is therefore a poor conductor. However, in natural conditions, it is rare to find water that is completely free of impurities. Rainwater, for example, can dissolve carbon dioxide from the atmosphere to form carbonic acid, which can further dissociate into hydrogen ions (H+) and bicarbonate ions (HCO3-), contributing to the water's conductivity.

In summary, the conductivity of water is primarily determined by the presence and concentration of dissolved ions, the type of ions present, and the temperature of the water. Pure water is not conductive, but the introduction of ionic compounds through natural processes or human activities significantly increases its ability to conduct electricity.

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It's those dissolved ions that can conduct well - and when water contains many dissolved ions, those ions make a good conductor. ... Pure water is a relatively poor conductor of electricity. However, water also is a very good solvent for ionic molecules such as sodium chloride (table salt).read more >>