What is measured to determine the amount of dissolved salts in a given amount of liquid?

Salinity is the measure used to determine the concentration of dissolved salts in a liquid, particularly in oceans and bodies of freshwater. It is typically expressed in parts per thousand (ppt) and represents the total amount of dissolved salts present in the water. This measurement is crucial in oceanography because it influences various environmental factors, including water density, circulation patterns, and the overall health of aquatic ecosystems.

In contrast, tidal range refers to the difference in height between high tide and low tide, which is not directly related to the concentration of dissolved salts. Tidal datum is a reference point used to help determine tides at various locations and does not pertain to the measurement of dissolved salts. An amphidromic point is a location in an ocean where the tidal range is theoretically zero; it is associated with tidal waves but does not relate to salinity. Therefore, salinity is the specific measurement that directly correlates with the amount of dissolved salts in a liquid.