Answer / priyankar talukdar

V sonic,G = SQRT(κ*R*T/MWG)
is the sonic velocity if only gas is present (presence of liquid ignored)[m/s]
where:
R is the gas constant (8314 J/kmol/K)
T is the absolute temperature
κ is the ratio of the specific heats (Cp/Cv)=1.4 for most of diatomic gases
MWG is the mean molecular weight of the gas phase

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