Hybrid nanofluids (HNFs), due to their superior thermal conductivity and heat transfer performance compared to conventional fluids and simple nanofluids, have attracted increasing attention in diverse engineering and industrial sectors including microelectronics cooling, chemical and manufacturing processes, biomedical devices, and microfluidic systems. The present article discusses thermal convection and mass diffusion in radiative hybrid nanofluid (HNF) flow over a sheet, considering Joule heating, chemical reaction, and activation energy. Water (H2O) serves as the base fluid, while copper (Cu) and aluminum oxide (Al2O3) particles act as HNF. The governing partial differential equations are reduced to nonlinear ordinary differential equations through similarity transformations and solved numerically using MATLAB. The effects of key parameters in this article are illustrated graphically and in tabular form, with results validated against existing literature. The key findings useful for optimizing heat and mass transfer in applications such as chemical reactor enhancement, advanced industrial thermal management and electronic cooling. activation energy. Water (H2O) serves as the base fluid, while copper (Cu) and aluminum oxide (Al2O3) particles act as HNF. The governing partial differential equations are reduced to nonlinear results ordinary differential equations through similarity transformations and solved numerically using MATLAB. The effects of key parameters in this article are illustrated graphically and in tabular form, with validated against existing literature. The key findings useful for optimizing heat and mass transfer in applications such as chemical reactor enhancement, advanced industrial thermal management and electronic cooling.