Smith4046 said:Think you are correct. The three 3p3 electrons of P should be bonded to the three Cls, each one forming single bonds. That leaves the pair of 3s2 electons unshared. Haven't even looked at the other choices, since I feel PCl3 is the one.
If incorrect, please someone let me know.
Best of luck.
Steve
Lone pairs refer to pairs of electrons that are not involved in bonding and are located on the central atom of a molecule or ion. They are also known as non-bonding pairs or non-bonding electrons.
Lone pairs on a central atom can affect the shape of a molecule by pushing bonded atoms closer together, resulting in a distorted molecular geometry. This is known as the "lone pair repulsion" effect.
The number of lone pairs on a central atom can be determined by deducting the number of bonded electrons (from bonding pairs) from the total number of valence electrons available for the atom. For example, if an atom has 6 valence electrons and is involved in 2 bonds, it will have 2 lone pairs (6 - 2 - 2 = 2).
Lone pairs can play a key role in chemical reactions by acting as electron donors or acceptors. They can also influence the reactivity and stability of molecules, as well as the strength of intermolecular forces.
Lone pairs can be shared between atoms in certain situations, such as in resonance structures or in molecules with multiple bonds. However, lone pairs typically prefer to remain on the central atom and are not commonly shared between atoms in chemical compounds.