Draw the Lewis Structure for CCl2O with All Resonance Forms, State Its Formal Charge and Polarity, What Is Its Molecular Geometry?

To draw the Lewis structure for CCl₂O (dichloromethyleneoxide), we first count the total number of valence electrons. Carbon has 4, each chlorine has 7 (totaling 14), and oxygen has 6. Adding these gives:

• 4 (C) + 14 (2 Cl) + 6 (O) = 24 valence electrons

Next, we start by placing the carbon atom in the center since it can make multiple bonds. The structure begins with the placement of the chlorine atoms and the oxygen around the carbon:

Step 1: Connect the carbon to two chlorine atoms and one oxygen atom using single bonds. This uses 6 out of the 24 electrons:

• C-Cl (2 single bonds) + C-O (1 single bond)

Step 2: Place remaining electrons on the chlorine and oxygen to fulfill the octet rule. Each chlorine can have 3 lone pairs (6 electrons total). Oxygen will have 2 lone pairs (4 electrons) making:

• 24 total – 6 used = 18 remaining electrons

Step 3: With the single bonds, oxygen will also form a double bond with carbon to complete its octet:

• C=O (1 double bond with 2 electrons from C and 2 from O)

This gives us the following structure:

   Cl
    | 
   Cl - C = O
      

Resonance forms can be generated by shifting the double bond between carbon and oxygen and creating a double bond between carbon and one of the chlorine atoms, leading to the following forms:

   Cl     Cl
    |     //
   C = Cl    (when moving the double bond to Cl)
    |
    O

Next, we calculate the formal charges:

• Formal charge on Carbon (C): 4 – (0 non-bonding) – (1/2 x 6 bonding) = 0
• Formal charge on Oxygen (O): 6 – (4 lone pair electrons) – (1/2 x 4 bonding) = 0
• Formal charge on each Chlorine (Cl): 7 – (6 lone pair electrons) – (1/2 x 2 bonding) = 0

Thus, all atoms have formal charges of 0, making the overall charge of the molecule neutral. Regarding polarity, since we have two chlorine atoms bonded to a less electronegative carbon and a more electronegative oxygen, the molecule is polar. The dipole moment points toward the oxygen.

Finally, the molecular geometry can be determined. The central atom (C) has two bonded pairs (C-Cl) and one double-bonded pair (C=O). This results in a trigonal planar geometry with bond angles of about 120 degrees.

In summary, the Lewis structure for CCl₂O has resonance forms, all atoms have a formal charge of 0, the bond polarity is towards oxygen, and the molecular geometry is trigonal planar.