Question 4.8: Drawing an Electron-Dot Structure for PCl5 Draw an electron-......
Drawing an Electron-Dot Structure for PCl_5
Draw an electron-dot structure for phosphorus pentachloride, PCl_5.
STRATEGY
Follow the steps outlined in the text. First, count the total number of valence electrons. Phosphorus has 5, and each chlorine has 7, for a total of 40. Next, decide on the connections between atoms, and draw lines to indicate the bonds. Because chlorine normally forms only one bond, it’s likely in the case of PCl_5 that all five chlorines are bonded to a central phosphorus atom, placing 10 electrons around phosphorus rather than the usual 8
\begin{matrix} \underset{ \ \ \ \ ╲}{ \ \ \ \ Cl \ \ \ \ \ } \underset{|}{Cl} \underset{╱ \ \ \ \ }{\ \ \ \ \ Cl \ \ \ \ } \\ P \\ \overset{╱}{Cl \ \ \ \ } \overset{╲}{ \ \ \ \ Cl} \end{matrix}Ten of the 40 valence electrons are necessary for the five P-Cl bonds, leaving 30 to be distributed so that each chlorine has an octet. All 30 remaining valence electrons are used in this step.
Phosphorus pentachloride, PCl_5
