In water chemistry, what does increased ionic concentration do to conductivity?

In water chemistry, increased ionic concentration directly correlates with an increase in conductivity. Conductivity is a measure of water's ability to transmit an electric current, which largely depends on the presence and concentration of ions in the water. When more ions are dissolved in the water, they facilitate the flow of electric current; thus, higher ionic concentrations lead to heightened conductivity.

Ions carry charge and, as they move through the water, they enable electrical conductivity. Common ions such as sodium, chloride, calcium, and magnesium contribute to this conductivity. As their concentrations rise, the overall number of charge carriers in the water increases, resulting in higher conductivity readings.

The other options reflect misunderstandings of the relationship between ionic concentration and conductivity. Decreased conductivity or no effect contradicts the fundamental principles of water chemistry, where a direct correlation exists. Although erratic readings can sometimes occur in data collection due to factors like temperature fluctuations or measurement inaccuracies, this doesn't alter the consistent behavior of ionic concentration affecting conductivity. Thus, increased ionic concentration definitively increases conductivity.