Resumen
Stars form, die and eject the elements created by stellar nucleosynthesis. Chemical evolution models are the tool used to interpret the elemental abundances in terms of star formation rate and of the gas dilution or enrichment processes in a region or galaxy. The evolutionary history gives the final state of the gas and stars. In this work we present an update of our grid of models (Mollá & Díaz 2005, MD05). We now modify the infall law, obtaining a slower time evolution, and better results for the gas and star formation radial distributions. This also changes the resulting radial gradient of abundances.