The acoustic properties of highly concentrated H(2)SO(4) are investigated performing visible and ultraviolet Brillouin scattering measurements. We analyzed the isotropic and anisotropic spectra of this molecular liquid in a wide temperature and exchanged wavector range in order to study the evolution of its sound velocity and viscosity. This allows us to extract the parameters required to describe its viscoelastic relaxation behavior. We found that the behavior of the hydrodynamic parameters of this molecular liquid shares some similarities with that of water indicating a rather high increase of sound velocity if compared to that measured by ultrasonics.