Adsorption and desorption of nickel on a passive carrier - graphite monolayer on iridium and its interaction with CsCl molecules are studied. It is found that on this surface nickel exist in two phases: in the form of physisorbed atoms and in close packed islands. It is found the that adsorption of Ni atoms on the 2DGF surface on (111) Ir (at T<1000 K) leads to the formation 3D-islands of these atoms. It is found that CsCl molecules dissociate on the surface of Ni islands. Using this experimentally observed fact, in this paper gives new method for determining the area of metallic islands.  Key Words: Monolayer, two-dimensional graphite films, CsCl molecules, adsorption, desorption