We carry out a statistical analysis of galaxy pairs selected from chemical hydrodynamical simulations with the aim at assessing the capability of hierarchical scenarios to reproduce recent observational results for galaxies in pairs. Particularly, we analyse the effects of mergers and interactions on the star formation (SF) activity, the global mean chemical properties and the colour distribution of interacting galaxies. We also assess the effects of spurious pairs.Publicado en <i>Groups of Galaxies in the Nearby Universe. ESO Astrophysics Symposia book series</i>Facultad de Ciencias Astronómicas y Geofísicas