Product Name: Iron Oxide Yellow 313 Color Index: Pigment Yellow 42 C.I. No.: 77492 CAS No.: 51274-00-1 EINECS NO.:275-098-5 Molecular Formula: Fe2O3.H2O Molecular Weight: 177.71 Iron Oxide Yellow 313 Properties Iron Oxide yellow 313 main content is the ferric oxide, iron oxide yellow chemical formula Fe2O3.H2O, is one of the iron oxide hydrates. Redone Iron Oxide Yellow 313 is a common iron oxide pigment used in developing building materials, paints, rubber, asphalt, sports racetracks, paper, plastic and others.