The problem of determining the acoustic properties of dilute bubbly liquids is examined using the method of ensemble-averaged equations and pairwise interactions. The phase speed and attenuation of sound waves in the small-amplitude regime are determined as a function of frequency of sound waves including the effects of finite surface tension, small viscosity of the liquid, and non-adiabatic thermal changes, and compared with the experimental data available in the literature. An excellent agreement is found for frequencies smaller than about 1.3 times the natural frequency of the bubbles, but the discrepancy is substantial at larger frequencies.