2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/196497We present general exact solutions for two classes of exponential potentials in scalar field models for quintessence. The coupling is minimal and we consider only dust and scalar field. To some extent, it is possible to reproduce experimental results from supernovae.revised version. To appear Gen. Rel. GravAstrophysicsGeneral Relativity and Quantum Cosmologytext