Draw the Lewis dot structure for C2Cl4 (tetrachloroethylene).

The Lewis dot structure for tetrachloroethylene ({eq}C_2Cl_4{/eq}) can be drawn by following these steps: Step 1: Calculate the total number of valence electrons in the molecule. Carbon has 4 valence electrons, chlorine has 7 valence electrons each, so the total number of valence electrons in tetrachloroethylene is: 2 ? (# valence electrons of carbon) + 4 ? (# valence electrons of chlorine) = 2 ? 4 + 4 ? 7 = 30 Step 2: Determine the central atom and connect the other atoms to it. Carbon is the central atom in tetrachloroethylene. Each chlorine atom is connected to the carbon atom through a single bond. Step 3: Place the remaining valence electrons around the atoms to satisfy the octet rule. The single bonds between carbon and chlorine atoms account for 8 electrons (2 for each bond). Therefore, there are still 22 electrons left to place around the atoms. To complete the octets of all atoms, we have to form double bonds between the carbon atoms, and each carbon atom will be surrounded by two chlorine atoms. The remaining 10 electrons are allocated to form two double bonds. Therefore, the Lewis dot structure of tetrachloroethylene is: Cl | Cl H3C--C--C--C--Cl | Cl Cl where each bond represented by a line is a pair of electrons being shared between two atoms, and each dot represents an unpaired valence electron.