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.
Concentration - Molality. Though only one letter different than molarity, molality is a unique unit of concentration. It measures the moles of solute per kilogram of solvent. In an aqueous solution (i.e. one that has water as the solvent), the number of kilograms of solvent is equal to the volume of water used.