The general dependence of the sound speed has been calculated \({{c}_{s}}\) in a two-phase system, such as liquid + gas and gas + liquid, as a function of the concentration \(x\) of an additional phase and thermodynamic parameters of the mixture. It is shown that in limiting cases, when the concentration tends to zero or unity, formulas are obtained whose numerical values agree well with the known values for the sound speed in water and air. This formula is generalized to multicomponent systems. The found functional relationship is illustrated graphically \({{c}_{s}}\left( x \right)\) for the case of a two-phase medium, and its qualitative and quantitative agreement with the results of other authors is shown demonstrated.
