This study examined the effects of a pressure gradient that was exponentially increasing or decreasing on the mixed convection flow of viscous reactive fluids in a vertical tube between two concentric tubes with r = 0 and r = b. The nonlinear partial differential equation governing the flow formation are solved using the implicit finite difference form where all time differentials were calculated using the forward difference formula, and second order central differences were utilized to approximate the first and second derivatives. The impacts of several physical parameters, including shear stress, the rate of heat transfer, mixed convection, viscous reactive fluid parameter, activation energy, Prandtl number, and exponential decaying/growing pressure gradient on skin friction and Nusselt number were investigated. It's intriguing to see that raising the values of Frank–Kamenetskii (λ), mixed convection (Gre) as well as exponential growing pressure term increases the velocity fluid, However, in the case of exponential decay, the parameter drop also causes the fluid's velocity to diminish. The results also showed that a small bump in the viscous reactive fluid parameter considerably improves the energy profile.