Phosphorous (P) and chlorine (Cl) bond covalently to form the important industrial compound phosphorous trichloride. The diagrams below show the electron structures of phosphorous and chlorine.

Question

On left, a purple circle labeled P surrounded by 3 concentric circles. The inner circle has 2 small green spheres. The second circle has 8 small green spheres. The third circle has 5 small green spheres. On right, a purple circle labeled C l surrounded by 3 concentric circles. The inner circle has 2 small green spheres. The middle circle has 8 small green spheres. The outer circle has 7 small green spheres.
Which diagram shows how the covalent bonds most likely form in a phosphorous trichloride mol

Answer 1

To understand how covalent bonds form in phosphorus trichloride (PCl₃), we can analyze the electron configurations of phosphorus and chlorine.

1. Phosphorus (P) has 5 valence electrons (as indicated by the 5 small green spheres in the outermost circle). To achieve a stable octet, phosphorus can share three of its electrons with three chlorine atoms.

2. Chlorine (Cl) has 7 valence electrons (as indicated by the 7 small green spheres in the outermost circle). Each chlorine atom needs 1 additional electron to complete its octet.

In the bonding process:

• Each chlorine atom shares one of its 7 valence electrons with phosphorus.
• Phosphorus shares one of its 5 valence electrons with each of the three chlorine atoms.

Thus, in the covalent bonding of PCl₃:

• Phosphorus forms three single covalent bonds with three chlorine atoms by sharing one electron from each.

Based on this, the correct representation of the formation of covalent bonds in phosphorus trichloride (PCl₃) would involve phosphorus sharing its electrons with each of the three chlorine atoms. This would likely be shown in a diagram that illustrates these shared pairs of electrons between phosphorus and each chlorine atom.

To summarize, the correct diagram would show phosphorus in the center sharing its outer electrons with three chlorine atoms, with appropriate indications of the shared electron pairs (representing the covalent bonds).