Water drops on the hydrophobic surface of grass. In chemistry, hydrophobicity is the physical property of a molecule (known as a hydrophobe) that is seemingly repelled from a mass of water. (Strictly speaking, there is no repulsive force involved; it is an absence of attraction.) In contrast, hydrophiles are attracted to water.
Ocean salinity is generally defined as the salt concentration (e.g., Sodium and Chlorure) in sea water. It is measured in unit of PSU (Practical Salinity Unit), which is a unit based on the properties of sea water conductivity. It is equivalent to per thousand or (o / 00) or to g/kg.
The salinity of the water is measured with a CTD instrument (Conductivity, Temperature, Depth). The conductivity is used to calculate the salinity in conjunction with the temperature and depth (pressure) measurements.Seawater has an average density of 1.027 gm/cm 3, but this varies with temperature and salinity over a range of about 1.020 to 1.029.he salinity of the water is measured with a CTD instrument (Conductivity, Temperature, Depth). The conductivity is used to calculate the salinity in conjunction with the temperature and depth (pressure) measurements.