How to Draw the Lewis Structure of Cl3PO?

To draw the Lewis structure for Cl₃PO (trichlorophosphine oxide), follow these steps:

1. Count the total number of valence electrons. Chlorine (Cl) has 7 valence electrons, phosphorus (P) has 5, and oxygen (O) has 6. So, the total is:
   3(7) + 5 + 6 = 21 valence electrons.
2. Identify the central atom. In this molecule, phosphorus (P) is the central atom, as it can form multiple bonds and is less electronegative than oxygen and chlorine.
3. Draw single bonds from the central atom (P) to each of the chlorine atoms (3 Cl) and to the oxygen atom (1 O). This uses 8 electrons (4 bonds × 2 electrons/bond).
4. Place the remaining electrons around the chlorine and oxygen atoms. Each chlorine atom needs 6 more electrons to fulfill their octets, which uses all the remaining 12 electrons (2 electrons for each Cl).
5. Oxygen will also need 2 more electrons to complete its octet, so we place 2 electrons as a lone pair on the oxygen atom, fulfilling its octet.
6. Finally, ensure that phosphorus has a full valence as well. In this case, P has only 8 electrons, which is satisfactory since it can expand its octet.

The final Lewis structure shows a phosphorus atom centrally located, bonded to three chlorines and double-bonded to an oxygen atom, with oxygen carrying two lone pairs of electrons:

This structure demonstrates the bonding and electron distribution in the molecule Cl₃PO.