Question

Assertion Both BF3 and PF5 do not obey octet rule
Reason Both are electron deficient compound​

Answer 1

Answer: A True

BF3

​

:

In above structure, 'F' completes its octet by sharing one electron from 'Boron' While 'Boron' shares three electron from three 'F' atom and has only 6 electrons in outermost cell thus it has an incomplete octet.

Explanation:

Answer 2

Answer:

Assertion is true but reason is false.

Explanation:

It is really true that BF3 and PF5 do not obey octet rule and violate it as in both cases the valence or outermost shell of Boron(B) remains unfilled with total 8 electrons or it remains incomplete with total 6 electrons and in case if Phosphorus (P) its valence shell is over filled or occupied by more than 8 electrons. So they both disobey octet rule.

Reason is incorrect as BF3 is an electron deficient molecule but PF5 is an electron rich molecule.