What best defines alkalinity in water chemistry?

Alkalinity in water chemistry primarily refers to the capacity of water to neutralize acids, which is largely attributed to the presence of dissolved carbonate species such as bicarbonate (HCO3-), carbonate (CO32-), and occasionally hydroxide ions (OH-). These carbonate species act as buffers to resist changes in pH when acids are added to the water, making option B the most accurate definition of alkalinity.

The total dissolved salts in water, while related to overall water chemistry and impacting various properties, does not specifically address the acid-neutralizing capacity of the water and thus does not define alkalinity. The pH level is a measure of the acidity or basicity of the water but does not encompass the concept of alkalinity itself, which is more about the water's ability to resist pH change. The concentration of nitrogen compounds, although important in discussing water quality and nutrients, is unrelated to the concept of alkalinity specifically.