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[1],[2]: In engineering practice, the Salinity is often measured in [ g/L ] and [ mg/L ] but as equivalent of ppk and ppm correspondingly.
But this is a misnomer as these units have a physical meaning of density while the standard Salinity measure is a dimensionless quantity and frac, wt%, ppk and ppm should be used instead.
The equalities [1] and [2] take the true meaning only when non-saline fluid has a density of 1 kg/L which is close to the distilled water density at Standard Conditions (0.9991 kg/L).
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