The coordination number of a complex refers to the number of ligand atoms directly bonded to the central metal ion. In the given complex [Co en 2Cl2]+, the central metal ion is cobalt Co .Ethylenediamine en is a bidentate ligand, meaning it can form two coordinate bonds with the central metal ion. Since there are two en ligands in the complex, they contribute a total of 2 x 2 = 4 coordinate bonds. Additionally, there are two chloride Cl ligands, each forming one coordinate bond with the cobalt ion. Therefore, the coordination number of the complex is 4 + 2 = 6.As for the geometry of the complex, a coordination number of 6 typically corresponds to an octahedral geometry. In this case, the cobalt ion is at the center of the octahedron, with the two chloride ligands and the four nitrogen atoms from the two ethylenediamine ligands occupying the six vertices of the octahedron.So, the coordination number of the complex [Co en 2Cl2]+ is 6, and its geometry is octahedral.