$$ \mathrm{C}_{2} \mathrm{Cl}_{2} \text { , which is connected } \mathrm{Cl}-\mathrm{C}-\mathrm{C}-\mathrm{Cl} . $$

To start with, we need to calculate the number of electron domains for each carbon and chlorine atom. An electron domain is an area where electrons are likely to be found, which includes lone electron pairs, bonding electron pairs, and multiple bonds (double and triple bonds). For the carbon atoms in C2Cl2, there are three electron domains each: one from the double bond between the carbon atoms and one from each single bond with the chlorine atoms. For the chlorine atoms in C2Cl2, there are a total of four electron domains: one from the single bond with the carbon atom and three from the lone pairs of electrons on the chlorine.

VSEPR (Valence Shell Electron Pair Repulsion) theory states that electron domains around an atom will arrange themselves in a way that minimizes repulsion, dictating the shape of the molecule. Using VSEPR theory, we'll determine the electron geometry and the molecular geometry of the carbon and chlorine atoms in the C2Cl2 molecule. For the carbon atoms with three electron domains (one double bond and two single bonds), the electron geometry will be trigonal planar, and the molecular geometry will be also trigonal planar, as there are no lone pairs on the carbon atoms. For the chlorine atoms with four electron domains (one single bond and three lone pairs), the electron geometry will be tetrahedral, and the molecular geometry will be trigonal pyramidal, as there is one bonding and three lone electron pairs.

Finally, we will combine the molecular geometries of the individual atoms (carbon and chlorine) to find the overall molecular geometry of the C2Cl2 molecule. Since both carbon atoms have a trigonal planar geometry, and the chlorine atoms have a trigonal pyramidal geometry, the C2Cl2 molecule will also have a planar geometry. The Cl-C-C-Cl atoms are all in the same plane, with bond angles close to 120° for the carbon atoms and slightly less than 109.5° for the chlorine atoms due to the presence of the lone electron pairs. The overall molecular geometry of the C2Cl2 molecule is planar with the Cl-C-C-Cl atoms are all in the same plane.