3. Equation of state for seawater

A physico-chemical system in equilibrium can be described by an unlimited number of properties: temperature, pressure, density, viscosity, dielectric constant, refractive index, etc. However, this information is redundant, as the system is completely described by a limited number of independent variables. However, this information is redundant, as the system is completely described by a limited number of independent variables. This number, or variance $\upsilon$ , is fixed by the phase rule: $\upsilon =n+2-\phi$

with n number of independent components,

$\phi$...