The critical volume provides data which may be tested for additive relations.
To Landolt is due the proof that, Additive reiations.
Other physical properties of these solutions, such as density, colour, optical rotatory power, &c., like the conductivities, are additive, i.e.
Kopp, begun in 1842, on the molecular volumes, the volume occupied by one gramme molecular weight of a substance, of liquids measured at their boiling-point under atmospheric pressure, brought to light a series of additive relations which, in the case of carbon compounds, render it possible to predict, in some measure, the cornposition of the substance.
The molecular volume is additive in certain cases, in particular of analogous compounds of simple constitution.