High-precision calculations of a series of standard models of the internal structure of the Sun using different opacity tables are presented. The models are compared on the basis of two key parameters - helium abundance and specific entropy in the convection zone. The effect of opacity on these two parameters in the radiative interior of the Sun is studied. Comparison of standard models calculated using different opacity tables shows that the specific entropy in the envelope diminishes with growing opacity in the radiative zone, while helium abundance grows with increase in opacity in the core. Investigation of static nonevolutionary models with modified opacities indicates a general connection between the specific entropy in the envelope and opacity in the radiative zone, outside the region of energy release. INTRODUCTION The classical problem of modelling the internal structure of the Sun has not lost its urgency due, on the one hand, to continuous revision of theoretica..