Question

Which of the following molecules will have unequal bond lengths?

• A. $N{F}_3$
• B. $B{F}_3$
• C. $P{F}_5$
• D. $S{F}_6$
• E. $Si{F}_4$

Answer 1

Answer: (C)

$P{F}_5$ molecule will have unequal bond length. In this geometry the equatorial bonds (2.04 A) are slightly shorter than axial bonds (2.19 A).