http://repositoriodigital.ipn.mx/handle/123456789/2233 Sat, 18 Apr 2026 18:40:32 GMT 2026-04-18T18:40:32Z http://repositoriodigital.ipn.mx/handle/123456789/6988 Title: Estequiometría Authors: Escorcia Arana, Andrés Thu, 20 Sep 2012 00:00:00 GMT http://repositoriodigital.ipn.mx/handle/123456789/6988 2012-09-20T00:00:00Z