A numerical investigation on steady external axisymmetric viscous flow and heat and mass transfer at the surface of an inviscid spherical gas bubble has been carried out. The numerical code developed for this study employs a velocity-pressure formulation combined with a finite-volume discretisation of the Navier-Stokes species continuity and energy equations written in a non-orthogonal body-fitted coordinates (BFCs). The code is validated against two types of standard flows, namely the flow through a diverging Roache channel, and the flow, and heat and mass transfers around a rigid sphere for the Reynolds number range from 1 to 300. On the same basis, the external flow, heat and mass transfer at the surface of an inviscid spherical bubble is simulated numerically and compared with the results for a similar rigid sphere. There are distinguishable differences in both the flow fields and concentration (or temperature) distributions around the bubble and the sphere.