THERMODYNAMIC PROPERTIES OF A MIXTURE OF HE AND N-2 AT HIGH-PRESSURESDETERMINED FROM SPEEDS OF SOUND

The equation of state and heat capacity of a mixture of He and N-2 Of equal composition have been determined at temperatures from 156.15 to 298.15 K and at pressures from 200 to 1000 MPa using a recently develo ped computational method. This is based on stepwise construction of rh o T isobars starting from an experimental reference p rho isotherm and using the previously reported sound speed data of the mixture as a fu nction of pressure and temperature. The derived p rho T data have been fitted to a new empirical equation of state for the mixture with a r. m.s. deviation of 0.02%.