The Lewis electron-dot structure of phosphorus trifluoride gives the central P

The Lewis electron-dot structure of phosphorus trifluoride (PF3) is a diagram that shows the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule. Here's how to draw it:

1. Identify the total number of valence electrons. Phosphorus (P) has 5 valence electrons and each Fluorine (F) atom has 7 valence electrons. Since there are 3 Fluorine atoms, the total number of valence electrons is 5 + 3*7 = 26.

2. Identify the central atom. The least electronegative atom is the central atom, which is Phosphorus (P) in this case.

3. Draw a skeleton structure of the molecule. Connect the central atom to the surrounding atoms with a single bond (represented by a line). This will look like P in the center with three F atoms surrounding it.

4. Distribute the remaining electrons as lone pairs. Start from the outer atoms. Each bond takes 2 electrons, so we have used 23 = 6 electrons for the bonds. We have 26 - 6 = 20 electrons left. Each F atom will take 3 lone pairs (6 electrons), so we have used 36 = 18 electrons. We have 20 - 18 = 2 electrons left, which will be placed on the central P atom.

5. Check the octet rule. Each atom should have 8 electrons (including the shared electrons). In this case, each F atom has 3 lone pairs and 1 shared pair (8 electrons in total), and the P atom has 1 lone pair and 3 shared pairs (8 electrons in total).

So, the Lewis electron-dot structure of PF3 will have P in the center with a single bond to each F atom and a lone pair, and each F atom will have three lone pairs.