The Lewis diagram is shown for PF5. What is the geometry associated with this molecule?

A. Tetrahedral
B. Trigonal bipyramidal
C. Octahedral
D. Trigonal planar

Question

The Lewis diagram is shown for PF5. What is the geometry associated with this molecule?


 		A.	Tetrahedral
 		B.	Trigonal bipyramidal
 		C.	Octahedral
 		D.	Trigonal planar

vera_ewing · Answer

@aaronq

vera_ewing · Answer

attachment

aaronq · Answer

you have to use VSEPR. For this question, theres only 1 possible answer in the options because of the number of atoms present.

vera_ewing · Answer

well since there are 2 on most of the sides the answer is A right? @aaronq

aaronq · Answer

how many ligands (atoms other than the central atom) are there?

do you know these shapes?

vera_ewing · Answer

@aaronq 2 and yes i know the shapes

aaronq · Answer

no there are 5 ligands

vera_ewing · Answer

@aaronq ohh so it's B right? because 2+3 is 5?

aaronq · Answer

yep, there are 5 F's around the central atom P with no lone pairs.  So the general VSEPR formula is $AX_5$